MikeFerrara:And to this we should add Bill Main, Bill Gavin and all the rest of that group. We shouldn't leave out Greg Flanagan either.
Someone indicated earlier in the thread that they didn't think cave divers changed diving for them but that's where many inovations came from...bc's, manifolds, alternate or backup regs, backplates (as we use today) and who knows what else. the NSS cave diving manual has a neat chapter written by Sheck Exley detailing the development of lots of the equipment we use today. If I remember right he gave credit for the first alternate second stage to Hal Watts.
Don't forget cave divers were some of the first (and certainly the first "group") recreational (as opposed to commercial) divers to adopt the use of Nitrox and Trimix.
Or that Sheck Exley was the the author of some of the first desktop decompression software- "Dr. X".