I feel notching is ok against other notchers, in fact, my favourite type of BnG is notching vs notching, the skill and tactics to outsmart and outplay your opponent choosing the right hides, using right shot at the right moment, is the best type of competitive BnG there is, if you are playing to win. (Not if you are playing purely to enjoy BnG and not care about winning or statistics.)
Anyone who wants to play BnG just for fun, won't like notching, anyone who notches wants to win, anyone who doesn't want to win, shouldn't complain about it...
The only definate way of telling if someone is notching is if they are moving the cursor notch by notch and counting the notches to the desired number, because for example, a certain amount of notches will go a set distance with a set power, 4s full power grenades are the most basic and simple shots to notch flawlessly if you know exactly what you are doing.
People can "notch" without "notching", by this I mean, have the angles memorised, or simply have markings on their screens, there is no way to prove if anyone is doing this, so there is no way we can ever have a rule against notching without fair/unfair accusations and/or punishments.
Back when I used to play BnG with only notching hardly anyone knew about it, and I stopped using it because I felt it was an unfair advantage, it's kinda like my opponent bringing a knife to a gun fight... Currently alot of players are notching, some are honest and open about it, others are not and hide the fact they actually do notch or know how to, either way, but i've started notching again recently against other players who know notch or play "lame" cuz I don't actually think it's lame, I think it's fair game, I will still never notch against players who don't know how to notch or zook distances.
In the end anyone can learn how to do it, anyone who wants to learn feel free to grab a few games with me and I will teach you the basics, I feel it's better to know notching and not need it, to need it and not know it, besides, it is actually fun when you get the hang of it lol.
And like Ray, i'm just trying to get on with it lol, no one liked me complaining about it, so now I am doing the opposite, let's see shall we?