I talked to my buddy who also uses slick tricks and he has seen no such problems. He has taken 34 deer and used Muzzy's up until this year.

It is his opinion that it was more likely due to hunter error in taking a shot at a deer at too steep an angle.

And on a side note:

Regardless of the thing you are trying to study, you need to have 100 times the date we have been presented to make any kind of valid conclusion. Say 100 guys here use Slick Tricks and have taken 1.5 deer per person were talking 150 shots and 2 deflections. But if there have only been 10 quartering shots and 2 deflections THEN we have a problem.