Fragging guidelines, note this is *MY* fragging guidelines not official club policy. (i.e. something I would do)
My SPS rules
"sticks" (acropora or montipora) should be a MINIMUM 1" in length regardless of how rare the coral is.
Encrusting corals (sps or LPS), should be minimum 1" x 1" size (or equivalent, basically the size of a frag plug (not the tiny plugs),
Plating corals (montipora caps are what come to mind) should be a minimum of 2" in any one direction.
"Bushy" SPS, pocillipora, stylophora (the good kind!), etc minimum 1" "broccoli floret" size
LPS, too many different types to really go over.
Softies, the most common is zoas, I would do a minimum of 5 polyps for the "smaller" variety, 3 for the larger kind. Things like mushrooms, base on how fast they grow, rarity, colors, etc. I do know that I don't like seeing that tiny button sized ricordia as opposed to a fuller sized one
Overall though the mindset is quality of quantity, rules are meant to seen more as guidelines than strict codes to follow. You could follow rules very strictly and do 1" sps frags, exactly 5 polyps, etc. And god knows I have seen more than enough frag swaps with a crap ton of pink birdsnest frags from one individual. But my mindset is if it grows fast give a lot. People are going to be more happy with a 3" digitata frag that is multi-branching rather than a 1" single branch, where as on the other side of that if you have Super Rare Acropora Takeoutasecondmortgiosis then yeah that 1" is more than fine and going smaller than this could be seen as fine.