Combination punching...fluently and frequently. Correct footwork. Physical fitness. Appropriate defensive ability. Lateral movement. Diet and conditioning to fight at pace. Video footage... enableing tactics to be placed in order before a bout. The list goes on. As for the "people who witnessed Corbett/Jackson assuming SUllivan would beat both men.." What a cop out!! Correct me if Im wrong, Corbett belted the **** out of Sullivan, Sept 7, 1892. Reading the fight report, as listed by Nat Fliescher in 'John L. Sullivan.. Champion of Champions', 1952, Sullivan is a flat footed flop IMO. Please dont offer lame arsed excuses for Sullivan either. "He damaged his arm.. blah blah blah" He was not physically capable of defending against Corbett, Jackson, Godfrey, Goddard (in Australia whilst there), Paddy Slavin or any other man of close to equal size with ability. He drunk his abilities away, before showing talent against any negro or talented white man of the gloved era. Sullivan was a victom of EGO, ALCOHOL, BACK SLAPPING FANS, MONEY and ILLEGEBLE GOVERNANCE OF THE GAME IN HIS ERA.
Now that is a classic! Imagine Fitzimmons with Toneys Pysical fitness and training ethic. He would be a 230lb beast! Untouchable in the day.
Tom Shakey's weight was 183 pounds when he meet Jeffries, or say just 2-4 pounds less than Rocky Marciano's ideal fighting weight! I don't think you can say fighter A is too small, then suggest another fighter who was pretty much the same weight, but had even less reach and tale of the tape in other areas was not. So I ask you SuzieQ do you think 183-187 pounds is too small to be a top heavy in the 1970's to present or not? As a footnote, Johnson lost decsions to guys lighter than 185 pounds, and was out worked by lesser talents.