Curious thing about a very powerful jab...you push him out of range of your right hand. This is especially true if the force in your jab is the result of rocking your weight onto your front foot. Because, before you can move, you have to get the weight onto your other foot.
Marvin Hagler was an interesting jabber, cause he could switch stance. He had maybe also the best southpaw jab or Pernell Whitaker.
Foreman kept jabbing Holyfiled out of range of his right. I dunno if he was fast enough to get all his weight into those blows lol! But when he did unleash power shots, Evander said he thought all his teeth were knocked out once, & Gerorge hit him the hardest of anyone.
Okay, I recognized now most powerful jab. I thought best jab. I would say Liston, Foreman, Lewis and Bowe had very powerful jabs.
At Heavyweight, Liston or Foreman. At a few feet, Tony Sibson breaking John Breen's nose at Wolves Civic or Colin Jones breaking Lloyd Hibbert's with 16oz gloves and headgear sparring. No jab, no game.
Wlad and is extremely fast as well. Liston, Foreman, Lennox, Bowe and at the lower weights Oscar, Hearns and Quartey.