Not quite. CS paths are heavily pre-programed. I do think you're right in that there is some adaptation, but nothing hectic. True pathfinding is mostly seen in RTS games - generally some variation of the A* algo is used.Well if they were programmed with some kind of 'learning' algorithms then yes they could but it would still be limited.
AFAIK counter strike does this with the bots in a way with the pathfinding. You load a new map and it takes some time to map routes for the AI. But I guess this isn't really 'adaptive' AI.