I don't see any. Hand to hand combat is such an ancient art, and the consequences of failure so severe, that I think trainers look for successful techniques from the past much more than they try to innovate. Due to the long history of boxing, a trainer can incorporate a wide variety of techniques and philosophies to create what he/she considers to be optimal.
I suppose it depends on what you mean by revolutionary; I think Nazim's towel can be quite useful, and more than a few trainers (Nacho and Nazim come to mind) use the foam pool tubes, which I do not think was popular at all until recently. Pedro Diaz seems to do very effective mittwork; he simulates the movements, rhythm, and intensity of a fight much more with Cotto than any other trainer I've seen. His improvised shadowboxing drills show some of the same things; they look like conditioning, but they are no doubt also reinforcing fundamentals. His tennis ball-catching also looks to improve coordination, and thus, sharpness in boxing.
I hate to alter the subject ever so slightly, but the conditioning of the 80s and 90s seems infinitely superior to today's supposedly "modern" athlete - I was watching Larry Holmes' fights, and I felt like these 200+ pound men were punching with the speed and intensity of someone like Cotto or Alvarez for 12-15 rounds. The tempo and pace of fights has really slowed considerably, and guys seem to get tired more quickly, too, especially above 160 pounds. I think too much reliance on strength and other aspects has created a sub par endurance boxing generation, and I can't reconcile that with the continual breaking of records in other sports. Some things don't really need absolutely revolutionary training methods.
Does anyone use those electronic punch bags? The ones in the shape of a human torso and head, which light up when you hit certain spots on the body? I'm guessing not. They look fun though.
if you learn to box from scratch, what would you expect to've learned before you're ready to spar; 'n what steps did you take to learn it?
The technique in boxing has been honed over many years which is why there is a universal training methodology. Stylistically there can be differences that belong to a certain gym, location etc. Emannual Steward and the Kronk gym produce a certain kind of fighter, Detroit,Philly, Europe, Mexico.hell! even Brendan Ingle in Sheffield tends to produce a lot of fighters that fight like Prince Naseem. The basics stay the same though, just like in every sport. If it ain't broke don't fix it.
A while ago, in preparation for the first Pascal fight I remember Dawson had this revolutionary contraption to help his boxing. It was like some bizarre exoskeleton suit that provided resistance when he punched. He would shadow box with it on. It looked quite cool and I don't think it had been used before.