There is one flaw with this argument, though: You can only sprint so fast, regardless of the keyboard you use, due to lag.
Wobble sprint is something I'm sure we've all had to deal with: I'll let you all in on a little secret: It's caused by attempting to start your sprint too quickly. The more lag you have, the slower you have to start your sprint to prevent wobble sprint. You can test this yourself by playing in your region and trying to start your sprint as quickly as possible after it breaks, and then doing the same in the most laggy region for you. Chances are, you'll get it more often, and it'll be worse, on the laggy server.
Nobody gets a connection good enough to sprint as quickly as BSM does. Doesn't matter what keyboard you use, your internet connection is the true biggest factor, and nobody could even possibly obtain a good enough connection to go as fast as BSM unless they lived right next to the servers. BSM is meant to fix the buggy sprint by fixing the buggy wobble sprint. By doing this, it's getting rid of the restrictions that the rest of us have to go through, that vanilla Minecraft sets. Wobble sprint isn't random, it's a restriction on capabilities of the player, which sadly is set by who has the better internet connection. If BSM was in vanilla Minecraft, that'd be awesome, it would fix the problem of laggy players being at a disadvantage, but since it's not, getting past the restrictions set by lag is not allowed.
Because of this, it's entirely possible to catch a BSM'ing playing with absolute sureness. The problem is that it still proves to be incredibly difficult, and there will be some really iffy bans due to the nature of it. The only time I'm completely sure of it's use is when fighting someone, because the use of it completely messes up the way me and some other top players fight, but sadly, this doesn't make good evidence because of the nature of how I fight. (Not looking at the opponent a lot of the time.) (Me and Sixzo did some testing on a private server once. It was about 50-50 who won in a normal fight, but when one or the other used the mod, they won nearly every time with usually 3-5 hearts to spare.)