I hear that your favorite athlete is Jack Dempsey.  Why is he your favorite? 
Because he was so poor if he didn't win the fight he didn't eat he would have to starve he won the heavyweight title kn his early 20s
It always impressed me that he started boxing under the name Kid Blackie. When did he start fighting under his name Jack Dempsey?
he use to get around by hanging underneath trains looking for people for bare knuckle prize fights, in one of his none documented fights he said he was floored 30 times but kept getting up, he had 100s of these type of fights before eventually becoming professional and having a documented record under the name Jack Dempsey 
Have you ever been able to visit Jack Dempsey's Corner  in New York? 
No, i would love to though, i bet Mike Tyson have because Dempsey was his idol Tyson looked up to him so much he dressed like him same black shorts and black shoes with no socks 
From what I understand Mike Tyson used the Dempsey Roll, along with Mike Zambidis. 
That is true.he fought 6 times in 2 weeks , he even fought a fight that he lost by KO that he took after not eating for a whole week..he later rematched the same man when he wasnt hungry and poor and won by knockout
I am sure that during his rough early years Tyson must have learned to be tough. I am sure he was always grateful that Cus D'Amato found him and helped him. 
Cus is a legend ! also Dempsey He was one of the biggest superstars on the planet at the time
They were definitely both legends, and I also value those that lead by example such as Cus did.