Nicely done!
I was weird, starting out I got the drag triplet immediately but couldn't figure out a normal triplet, even after checking out videos etc, until a friend showed me in person.
How and when to use it? That's a matter of taste and everybody's aural palate differs. Experiment with it and try to throw it in at different points in a line to see what works for you and what doesn't.
For me the challenge was to work it in when I wanted to, and now that I can, the challenge has become to make it smooth and accent a line rather than interrupt a line. For me it's fun to start with a drag triplet on a hiccupy syncopated section, or to finish such a section with it.
For example, Al Gare's descending line in "Johnny Got A Boom Boom", below at 1:20 and 1:45 (and at the end of the clip), he just plays a straight pull off the bottom G before hitting the open A – I like to throw in a drag triplet on that G before snapping the open A.