with my modest experience and knowledge of building and aerodynamics, im totally disagree with the idea that square TE avoids flutter...A square surface is absolutely the opposite to an aerodynamic surface!

if you use a square TE is because you are a begginer, a lazy builder or youre trying to prevent the airplane from the hangar accidents
its suppose that the air should flow softly and the airplane must have accurate edges deppending if it is the LE or the TE, of course the uses are different
have you ever seen a full scale aiplane with any square edge or surface? i dont think so, and the guys who desing them konw something about aerodynamics...( the word I use is ENGINEER )

with the exeption of the F 117 stealth of course, but the objective is another one in that ship
there must be lots of reasons that produces flutter
but try to see ANY TE of a wing profile.....they re not square!

ok...lets take a look to the masters of flight; have you seen a bird with square feathers???

i havent
well, sorry if this message became i bit rude, but its my opinion , if any engineer say it its true and proves it on a wing tunnel, MY APOLOGIES
sorry for the english