I guess I've been lucky. My beardie's strategy seems to be to use his tongue to capture his CRX (CRickets and CockRoaches and CRunchy CReepy CRawly CRitters) and then chew them up once he gets them in his mouth. So it seems like I'm fairly safe when I'm feeding him just as long as I don't stick my fingers in his mouth, although I've had my fingers zapped with his little sticky tongue a number of times.
Back in the day before we swore off superworms, I used to give them to him on a little plate (after I rolled them in vitamins and calcium), so my fingers were out of the "strike zone".
And BTW, mine has never been very good at chewing his food thoroughly. They're all different -- some you can get away with hand feeding more than others. You were wise to disinfect -- glad too hear it didn't hurt for too long.