While running through a quick game earlier today I ended up in a position where there was a life crystal about 10 squares away from any nearby cities.  Ran a pioneer up to try and put a city next to it since Relias had declared war and I didn't feel like putting troops on an outpost, find out none of the squares in the area provide grain.  Okay, whatever, I just use the pioneer to build an outpost and claim the crystal before moving on with life.  About 20 turns later, Relias runs a pioneer around my city and heads up there, dropping a city 2 squares off the crystal on a tile that I previously checked and know for a fact did not provide any resources.  Que?