Yes, it is usable on the handle mount. The TA11F come with a TA51 flattop mount included, just separate the TA11F from the TA51 and mount the TA11F in the handle the same as any other ACOG.
Your BDC (bullet drop compensation) reticle will be off; but since the BDC is designed around a specific barrel length, mounting position and ammo type, it was probably going to be off anyway. (I believe the TA11F BDC is designed for M855 out of a 14.5" barrel on a flattop mount)
I really wouldn't sweat the BDC too much. the key is just to sight it in with the type of ammo you intend on using and then learn the deviations from the BDC at longer ranges and with different types of ammo. For about 99% of your under 300m work, you won't even need to do that - just put the reticle on the target and you are good to go.