I fudge enemy stats all the time, or at least I used to. These days I play blades in the dark, and before that I no longer needed to fudge much after years of practice.

The argument about fudging usually presumes some sort of pity for injured players and creates a strawman out of that. I don't fudge hits or misses to save people, I fudge to keep the fight moving along. Six rounds of "your sword clatters against its scales but it seems to be holding up okay" gets old really fast. If the fight is taking too long I whip out some kind of tension ramping effect and drop the enemy hp. "Oh no, it dumps over a cauldron of acid! (But it only has 20 hp left not 60 because this is getting slow)"