Well then I'm in for a world of pain, last summer was surgery on a torn bicep and labrum plus multiple hamstring tears over the years.
So, I am currently on a week of aggressive PT to fix this leg issue once and for all. Currently involves doing foam rolls for side, upper thigh on a baseball, and then laying on a baseball, then golf ball, so it gets up under the hip.
Don't know about Graston, but this hurts like fucking shit. Then it feels great after. You have mentally tell yourself you're not re injuring yourself doing this, or it's hard to make it hurt enough.
If you have hammy issues, I suggest standing and rolling a baseball under your foot for a minute or so. Loosens up the posterior chain.