Ok, I didn't think this was a real problem at first, but the many threads have convinced me it can be (assuming an entire group of players optimizes for this).
An alternative to fixing it other than capping at 5 hits could be something along the lines of 'This power always misses on a natural roll of 1-4'. That could bring the math back in line no matter how much anyone optimizes but still leaves room for that awesome lucky shot your players will talk about for years.
An alternative to fixing it other than capping at 5 hits could be something along the lines of 'This power always misses on a natural roll of 1-4'. That could bring the math back in line no matter how much anyone optimizes but still leaves room for that awesome lucky shot your players will talk about for years.