Biggest Names That Conn Possibly Beats AtHeavy?

Hell no.
Moorer KOs him.
It's a toss up vs Schmelling.
Dempsey KOs him.
Tunney outpoints him.
Patterson KOs him.

 

Liston sends his head into orbit.

 

Foreman decapitates him.

 

Crazy

 

I don't agree with White Bomber the majority of the time but his picks here are solid much as it pains me to say. Crazy is picking Conn over Dempsey and Marciano.

 

When?

 

Gibbons was a better win than Conn would have been.

 

I have seen folks list Tua as fast, at least of hand.
But he was not glacial, & not below average hand speed for a modern HW.
To be that slow you gotta be comeback Foreman or slower.

The "could" in the question means we literally could pick many who have a small to remote chance, a better way to word it would be something like "has a decent chance", or say at least 1/3 odds.

Many are as heavy or more than prime Tua-especially if you are going by weight, which was what you indicated-& are not slow.
Use height per weight or body fat percentage you are closer to the truth, but you must know that some with even more body fat are not slow-like Tyson Fury, whose hands are fast for a HW not even considering his size.
Even Ruiz has relatively wuick hands...

 

He "Could" beat Joe Louis. Almost did it too.

 

It really has nothing to do with handspeed if your feet can't get you in position to land a punch.

 

Sure, but Tua & many guys were not that slow-some big guys are pretty fast.
Could Conn stay away long enough to decision Tua?
Maybe, but "The Terminator" would be much nest incarnation as mere "Tuaman".

 

Conn would leave that guy thinking that he was shadowboxing. Tua moved slow and thought slow.

 

I do not know if he was slow witted, although Ali famously got a very low score on an IQ test & embarrassed said "I said I ws the greatest, not the smartest". But he obviously was smart in many intuitive & boxing ways.
Tua did not have slow hands.
He also was not a slug when he was helping break a record for most punches in a HW fight, & among the top in another bout.
Yet sure Conn was faster.
Louis did not have fast feet, & caught up with him despite being foolishly dehydrated.

Perhaps Conn is the minimal weight someone can be & bear up under whatever Tua manages to land.
You would cite peak Jones too, although rehydrated he was bigger.

 

I don't think Conn was clearly better than Gibbons.