I don't think the SB MCH was fluid, or even fun to play, and like the summoner today, some people used to love it, but theses people aren't a majority, and probably devs didn't like it either.
-> Having full reload to be 1-2-1 to make us able to quick reload just after to be 3-2-3 wasn't intuitive.

And maybe sad but true, but dev always got the last word on their games. If a class is unpopular change it is probably better than keeping it same.