I personally do on occassion. I work at a hospital and run into violent patients on my unit every once and awhile. Due to the nature of their conditions, most are not even aware they are being violent. Obviously nothing greivous is used, mostly control measures and lots of soft checking and limb entanglements. Generally we like them to leave healthier than they arrived. I've been punched a fair amount, kicked, grabbed and pushed.
My last encounter looked a lot like Iain Abernethy's karate gripping video. Luckily once I softly parried a punch to my chin and got his arms gently but firmly under control I was able to talk him down and get him into bed.
Does anyone else use their stuff for work and when was the last time you had to use it?