Beth, that's certainly an inspiring story! I've also been surprised at just how far I've been able to progress myself, considering I started ballet totally on a whim when I was 21 (I just turned 24 last week) and had no prior dance training whatsoever, though I did do gymnastics competitively as a kid. I have been working this last term towards my RAD Intermediate Foundation exam and my teacher is preparing me for pointework. I am TOTALLY floored that I got this far, I never expected that things like turnout and flexibility were something that I could actually improve on - for so long, slogging through all those beginner classes, I felt that due to my age I would just remain at a certain plateau and never improve beyond that. I never imagined I would make it past the Intro level, much less into pointe shoes.
Although, keep in mind that I take six dance classes a week (four ballet and two modern) and so this has probably had something to do with my progress, but as Beth mentioned, no matter how late you start, if you work consistently at it you WILL improve.
ETA: Beth, I just had a peek at your website and I had no idea you taught private lessons AND were in the NYC area! (I'm from New York myself, an East Villager...bwahaha.) I may just have to look you up once I'm back from New Zealand - hopefully my technique will be good enough by then to have something substantial to work with, haha.