I can confirm all of this. Nade throwing is really hard thing to get it working correctly in code, but... In current sources I'm trying at least to prevent bots to throw in accidently direction. Also they don't look so often at the wall right now. It's not perfect yet, but I believe it's a bit better at least. It has also some dark side - this what I'm trying right now with described above - I'm forcing them to "forget" enemy behind the obstacle more often, so sometimes they are surprised by the enemy they shouldn't be surprised.
Work in progress...