N810 I am also a LM player yet it is redicilous to say cupped hands is not too good for its cost.
1- the best on a dice roll is 5/6. So yeah I think it is risk free as it can be in Warhammer.
2- not once have I ever failed to bounce it because a wizard was out of LOS. Where are you casting the 7 dice spell? The fast cav on the right most flank?
3- Most of a miscast result means either %50 chance of death, D3 level loss or a large Str10 pie plate.
Maybe I should put it this way "Where is the risk in using the Cupped Hands vs not using it?" I don't see it.
With my suggestion
risk is what if I opponent rolls 5-6,5,8-9 which are relatively harmless hence waste of the item. Small template doesnt cover much when centred on the slann, one S6 hit is meh etc.
I don't know about you but I only bounce it on 1-4 and 11-10 which either kills the enemy highest level wizard half the time or makes him lose D3 levels.
TBO now I feel sad that I have created another 7 dice dweller double dip monster. The shame.... THE SHAAAAMEEEEE :P