I was a TTU student during Welker and Amendola's careers and the one thing that kept Amendola from reaching the status Welker had here was his inability to either run through the last tackle or make the last guy miss. Welker had that uncanny ability to finish as is evident by his Big 12 punt and kickoff TD return records. Amendola would always get by the first 10 guys then get tackled by his shoestrings by the last guy. He ended his career with only 1 TD on punt returns but got tackled on the 1 or by the last guy countless times
In my opinion what makes Welker great is his ability to move so quickly laterally and then transition to full speed almost instantly. Amendola does not have this quality. I think everyone is getting a bit overhyped about his potential to be the next "Welker".