I bend up on EGB and down on everything else. sometimes i bend down on G and B when on frets from 1-5 as there's more tension thus less distance to go through for the right pitch to come up.
i use my middle finger for bends very much, or the third with all the others supporting behind, though i tell my students to mostly use their third or fourth unless absolutely necessary. when they see my using my second, i just tell them to do what i say, not what i do. i have bad habits too but they work for me.
we all have a different body. some people have their nails right up against the edge of their fingers, mine need to grow at least 4-5 mm before they go past my finger and interfere with my playing. it's quite useful :D not that i enjoy having long nails. years of teaching showed me that people with hands like that aren't too common (around here at least)
I think pretty much like HTH's teacher thought, if it works, and sounds good, and doesn't hurt or limit your ability, it won't bother me. if it looks uncomfortable or the tone isn't optimum, that's when i nag.