So grenades have an arch to then and the AI calculates its thows with ONLY the arch.
this means the AI can and will trow over cover/ brigdes and generally can be rather competent when fighting from elevation.

...but thats kinda not fair. The player cant chuck grenades. We require line of site to aim the hit sphere.
This means the AI actual gets away with growing grenades while staying away from ledges and prevents overwatch. something the play cant do.
Im unsure if this issue is a issue with the AIs seeming better version of the grenade targeting, or an issue of the players lack of targeting.

Downgrade the AI or upgrade the player? not sure how that factors in to balance.