If you mean that they were loaded with some type of object or substance that was used to strike Jeffries harder with, then I'd say he would be subject to reevaluation.
I have read, although I can't verify this, that Jeffries did not have his fists taped inside his gloves, while Fitzsimmons did. It may also be that Fitzsimmons taped his hands in a certain way with questionable material. Jeff evidently knew about this beforehand, and didn't give a ****. (Imagine Billy Collins Jr. knowing all about what Resto and Panama Lewis were planning to do ahead of time, not caring anyway, and going on to win despite Resto's unfair advantage.) No, it doesn't change my assessment of Fitzsimmons, especially as he went on to dethrone George Gardiner for the newly created LHW Championship over 20 rounds at age 40. It does alter my perception of Jeff's chin and toughness however, that he could know about it, not care anyway, then prevail in striking fashion despite it.
Burns did something like that with Hart and got him angry so he fought stupid...... I think it's BS, like the loaded gloves of Dempsy vs Willard. one must think, Jeff was 20 pounds heavier than the huge 200 pound Sullivan. And at @170 I might want to even things up a bit giving away 50 pounds...I could be off five pounds or so...havn't looked it up.