When it comes to the term ham-handed, or ham-fisted - meaning 'to be clumsy with ones hands' - there are a couple of different battling etymologies (also the title of a new show on SyFy hosted by the least successful member of some boy band/comedy group).
The first comes from a name, believe it or not. Joseph Hamphist was a printing press engineer in the aughts who was responsible for a ridiculous amount of workplace injuries. (Just imagine him coming into work every morning, stamping his card, then banging his head on the '1 day since last accident sign, knocking the 1 off to reveal a 0.)
The presses themselves had to be stopped so many times, that not only was the term 'hamphisted' born, it also created the ever-popular saying, 'stop the presses.' Or the more accurate, lengthened version, "Stop the presses, Hamphist just took another shit."
The second of the battling etymologies (10 PM Central on Friday) is the story of Jerry the Butcher Tate, a face-punching engineer in the aughts who was responsible for a ridiculous amount of workplace injuries. (Just imagine a huge Irish-American punching someone in the face until they pee.)
Jerry was notorious for having smelly pork hands, and the gloves were so thin back then that other fighters would complain that when he jabbed, it smelled like a Sunday roast. There is even a famous caricature drawn of Jerry Tate that shows him ready for fisticuffs, with pineapple rings and cherries speared into his gloves. There was also a well-circulated cartoon of the Butcher in his corner of the ring and his opponent sitting in the center at a dinner table with his fork and knife in hand, table cloth tucked into his boxing robe.
Some would claim, incorrectly, that there is a sexual connotation to the term ham-fisted, either along the lines of doing a sexual act to a pig, or jamming a bunch of cold cuts into some well-greased lady parts, but these interpretations are inaccurate. Fisting wasn't even invented until a teenage David Hasselhoff got DRUNK, and that was some time in the sixties, probably.
Short Answer: What a bunch of nonsense. Obviously, fisting has been around since Caligula. Wait, boxing robe? Does that sound right?