I don't know nothing about that stuff..
First of all, I'm 5'10 as well, and started dunking in the 9th grade.. I'm, um, much older now, but can still dunk one-handed.. At any rate, I was doing specific exercises.. I'm not advertising, but I know that book from Air Alert has the same exercises in it that I was doing.. VERY GOOD book.. Just do the routine about 5 times a week, for 30 minutes or so, and it's golden.. At least for me it was.. I had a decent leap before the book, but I was doing the routine for about a month and REALLY noticed a difference..
Do a quick web search for Air Alert.. It's only like $15 or something like that..