> Someone who knows what they are doing can afford a few "lost concentrations" or skills missing or a few extra hits going through.

This isn't really true. The vet with non-perfect skills probably isn't going to die much more than he would with perfect skills, but he will likely kill slightly fewer people. When you're trying to trip someone to death and you "miss" a couple trips because your trip skill is at 75%? That makes it pretty easy for someone to get away.

The difference between "85% weapon, 85% second attack, 80% third attack, 85% enhanced damage" and "all 100% in all of those" is huge, as far as damage output. More damage output means a smaller margin of error for the people you attack, meaning you get more kills.

Now, most of those will go up "naturally" without spamming, but it *is* possible to artificially inflate them (somewhat) by just level sitting.

Sometimes a given matchup is so "tough" for your combo that you absolutely *need* your key skills to work in order to win (and avoid dying). For those situations, if your key skills are at a low percentage, then odds are you just avoid the fight altogether. So, having those key skills perfected means the vet can attempt that fight (and maybe win) where he wouldn't have otherwise.