Here's a thread "Save/load mania", concerning the free TBS Wesnoth. It supports my argument that adding save/load option has many downsides. Last time I played an early version of Wesnoth, I think it didn't have an option to save mid-game and I had to finish scenarios in one go.
http://www.wesnoth.org/forum/viewtopic.php?f=3&t=6321&st=0&sk=t&sd=a
People talk about reloading whenever a veteran unit dies etc, how playing without load affects their behaviour by making them more cautious and prepared players... It's pretty clear save/continue has a strong psychological and gameplay effect. People disagreeing with this are either not perceptive enough, or in denial. Especially that the thread starts with a poll, with predictable results. It's funny, because many of them reach a conclusion not using save/load made the game more enjoyable, and taught them to play better.
I fail to see why you post a thread where the Poll indicates that most people prefer to be able to load in the middle of a mission than not. And where a lot of people admit to reload because they don't want to lose a single unit or they don't find fun when they get a streak of bad luck and their units die in a "unfair" way... It is like you are going against yourself...
Btw, in my oppinion, a much better design to get the feeling of "becoming/playing better" are achievements. Some people love getting them and some people just play the game and don't care.
Bandwagon fallacy, a.k.a Appeal to popularity. By your own logic, Elemental should be a FPS game because it would sell more copies that way.
Your own poll supports me 
As far as I know Stardock makes games to earn money as all companies out there. And Save/Load seems to be normal choice in the mainstream TBS games (while Wesnoth and Dominions are nice, one is free and the other a cult hit at most). Adding a feature that appeals the masses is better than adding a feature that appeals a smaller subset of players.
And don't mix things together: TBS is a viable genre to make money as Stardock and other companies show. But as with any other genre, you need to do it well. There are plenty of FPS games that fail spectaculary or don't break even.
Do you have any argumentation behind your 'would be equally fun', or is it just 'because I say so' ? I can certainly see a lot of players reloading when a spell effect gives underwhelming result, whenever any truly bad random event happens, when you run into a strong enemy, when you lose your prophet or pretender in battle (lots of battle effects are chance-based so reloading would help against stray arrows etc).
This again: what's the problem reloading if they want to reload? Most times players play to have fun, so if they reload is probably because that's their way of getting more fun out of the game. Your whole speech seems to imply that there's something bad/wrong/un-fun reloading a game.
It's perfectly possible to make a game that follows a path less traveled with good results. Sometimes it's called innovation and many people like that. Fantasy General has no town or city building. Master of Magic has unit upkeep. HOMM doesn't have unit upkeep and it's one of reasons army sizes tend to be measured in weeks. Games use different approaches to many aspects, and often they're so different they're not comparable. It's impossible to say one is strictly better or worse.
And guess what? MoM and HoMM allow you to save games! (I don't remember FG, I played that game a looong time ago). Btw, FG doesn't "innove" much on my book, if you are a wargamer you know there have been very similar board games forever (and FG wasn't the first game from SSG either).
Save/load is the right thing to do in many strictly linear and deterministic games, because otherwise it forces replay and that's boring. Save/continue is a different approach. Neither is strictly better than the other, although I prefer save/continue for the reasons I listed. What's important is that they're both viable, and they're generally mutually exclusive - if you want a well designed game. Calling save/continue a subset of save/load is, for certain types of games, incorrect.
Some people think that not been able to reload to avoid some disaster, to test some crazy idea or just to show/remember later a "special moment" is boring. Also, in games with random chances, some people become frustrated when they think they have had too much bad luck and that the game has been "unfair".
Speaking as a CS graduate, I can't say I'm surprised or impressed that you can copy files. Fortunately, for most people writing or even downloading such scripts is not worth the effort and they learn to play with save/continue, which has many beneficial gameplay effects.
Doing a Windows Service in C# that uses FileSystemWatcher to modify the saves games directory would be pretty easy. And it could install with a double click. Not much effort there for the person using the mod.
And about the beneficial gameplay effects: it has beneficial gameplay effects for you, for me it has many negative gameplay effects.
If you can think outside the box, you realize that save/continue is not any worse than save/load. Objecting to a game being designed with this approach would be like objecting to not having construction options in Fantasy General, or not having upkeep costs in HOMM games. It's a premise, it's the point of entry. Fundamental part of game design. You either like it, or don't like it and pick another game. Things like this shouldn't be viewed in a technical 'feature checkbox' way - unless someone does something horribly wrong, like forcing players to pass 10 missions without saving, or having lives' limit in a logic game.
I can think outside the box and for me it's worse, because it's an artificial restriction that doesn't achieve anything valuable.
Not strange at all. TBS are a tiny fraction of the mainstream games. Take a look around. TBS are practically nonexistant in mainstream. Stardock is a team of skilled necromancers reviving extinct genre.
Then reading sales numbers, Galactic Civilizations 2 did surprisingly well given that they are "nonexistan in mainstream". I suppose the same can be said about Civilizations, HoMM,... But what it's surprising is that you are pushing for a feature that is less popular in a genre that according to you is highly unpopular, that seems a recipe for financial disaster.
Finally we agree on something. Yes, Master of Magic is a very un-replayable game (in the first turns)! Seriously, first few dozen of turns are terribly boring and schematic. Most of the time it's "Set taxes to 1.5, explore with your starting units for a while, scout with magic spirit. Build +population buildings (granary, farmers' market) and then +production buildings like sawmill and foresters' guild. Bulding miners' guild next will probably be the best choice. Only then Master of Magic leaves it's terribly boring stage and things start getting colorful. Until then, it's "next turn, next turn, next turn, next turn". For me it was the most boring part of each game, and it heavily discouraged me from starting a new game. Having the same queue for units and buildings didn't help. As opposed to Dominions3, in which a combination of save/continue with immediate action meant things are colorful from the word 'go'.
MOM was the only civ-like game I enjoyed, so I won't comment on Civ. I have no idea about MOO. I have only played Shadow Magic out of AoW games, and it suffers from the same design choices as MOM - initial construction phase is quite long and repetitive, discouraging from starting a new game. Having lenghty and schematic opening seriously harms replayability especially in a save/continue game, that's why making the beginning fun is even more important.
We must have played a different Dominions 3 because everything you said there applies to Dominions too. Build army, roll over neutral province, rinse and repeat with very similar armies and strategies until you find someone. In the meanwhile research or kill with your pretender (if it's not a sleeping pretender) and have "fun" accounting which mage has searched what type of site in each province... Yep, the same as the start of MoM, Civ and AoW.
If anything, it's an understantement. Many players reload when something less than optimal happens (such as only getting X from event Y). They may think they're having fun, but many discover they're boring themselves.
This is, for me, the failure of your whole argument: the majority are having fun for sure. For a lot of people Save/Continue limits the game in a way that becomes more un-fun than Save/Load. They don't want to think about the different 1000 combinations and what may happen 100 moves ahead and then lose because they didn't acknowledged posibility 1001, which, btw, was totally random and out of their control (becoming frustrated with the game in the process).
