What's sharp to me? Good question.
I was thinking my 8" utility needed sharpening. Then I boned a roast, don't recall needing to do a whole lot of slicing, or sawing, or anything. Fact is it went through the meat without much effort at all.
So even dull seems sharp enough. I should still take a stone to it ... I'm not as anal as many of you folks, but then I do work at home so thats a different perspective, from where I'm at I will say 'sharp' is where the knife does the work and without using so much force as to make using the knife dangerous. Like I say, different perspective, my Carpel came from using wrenches, not knives.
About taking knives someplace else, many people see bringing your own knife into their kitchen as an insult. Specially people like my Mother. So I'm ove ar Moms for New Years dinner, dig through two or more drawers piled with knives, Suppose to slice the pork but it comes out in shredded slabs, Ma says how she guesses she should get a sharp knife, I mention how I was thinking of bringing the slicer and BANG , Moms off to the races!