I've never cut at the muzzle...but...I do use the next larger caliber size patch to ensure there's always material well up around the circumference of the ball.
And in comparing commercial precut round patches to homecut square patches, I've never noticed any difference...IMHO, with the list of other variables involved with reloading each and every shot, I'd be very surprised if a definitive difference actually exists that could be attributed to that and that only.
In a similar vein, I've experimented with patches all the way up to 2.5" in diameter, with the excess folded back and forth over the top of the ball like the end of a coin wrapper, and never saw any ill effects of that...the huge patch simply flared open like a parachute and fluttered to the ground just 3-4 feet in front of the muzzle...as you know, given the exit spin rotation and velocity hitting the outside air is the equivalent of hundreds of mph wind blast