I've always disliked the concept of critical fails in general, and this is a great example of why. If we're to believe that our characters are truly these great warriors with far more skill and experience than an average person like the texts usually say, how does it make sense for these professionals to just completely blunder 1 in 20 of their attempts at everything? From an RP standpoint, it doesn't add up, and from a gameplay standpoint, it's just annoying as hell IMO.