I think that this quandry may better be solved by looking at the students and their feats rather than the master.
Daniel-san learned to paint. Daniel-san learned to wax the car. Daniel-san learned to drive...in the movie AFTER learning how to wax the car. Daniel-san learned the Crane Kick. Daniel-san learned to break a big block of ice. Daniel-san couldn't keep the girl in any of his installments. Daniel-san abandoned his teacher when his own life went a different direction.
The turtles mastered four distinctly different weapons with different tactics for the express purpose of killing their enemies. Whenever they fought, it was to the death. They killed Uroku Saki, the strongest warrior of the strongest ninja clan in modern Japan, after the prolonged battle of wiping out his army. They defeated an army of Mousers while keeping the girl (of a different species, mind you...not a different nationality) alive and safe--oh yeah, the one they managed to keep around for each of their installments, btw--through to another day. They were transported to an alien world after taking on an invasion force of disembodied brains disguised in android-like bodies while trying to search for the mysteries of their mutant origins, where they enjoyed a fiesty glass of Zim-CUK! before being transported off-planet when captured by bipedal Triceratopians...where they dueled one-on-one to-the-death with seasoned gladiators of the same Triceratopian race to an audience of thousands of interstellar beings in an environment with to-them-unbreathable-atmosphere...WHERE THEY EMERGED VICTORIOUS AND WENT ON TO ESCAPE THE ARENA BY TAKING THE TRIKE EMPEROR HOSTAGE. Let's not forget Dr.Honeycutt trapped in...you know what, let's just stop there.
Now you tell me, who's training produced the better students?