I don't know. But I know two things for sure:
1) What you observed is correct; I've seen the same.
2) If you put the botaim plugin back into action, the bots are pretty good again! All it needs is the parameter "bot_aim_fix 0".
This, however, brings up a question: Isn't the code of the botaim plugin supposed to have been integrated in the bot code, or did I miss something?
Without it, the bots are worse shots than me when I'm drunk beyond all limits, so the aiming code really needs some improvement.
Meanwhile, I suggest you guys use the botaim plugin to get more challenging bots...