We all talk about dropping shit but no one knows exactly what it means to actually drop something.
I think you're asking about what constitutes a "successful drop"???
That depends on who's defining "success" .. If it's Guinness, there's rules, & that would be why Ed's Alexandria drop wouldn't count (didn't he swim?) .. Everyone else is gonna define "success" a little differently. Those among us whove been around longer might look at style relative to inherent hazards. Newbies might just look at the big hole & all the spray, & whether or not the paddler came out the other side.
The only time I ever really care about anything like that is when/if the paddler is being obnoxious about having run something, like "Yo you all see how rad I am? Check me out styling that ginormo waterfall! Dig me!" .. That's when I'm like "Hey guy, you pulled a burning man & landed on your head ..."
Again, check out the BT thread & see what those guys said on all this.