Roberto Duran gradually jumped from LtWeight to WW. Duran defended in DeJesus 3 in early 1978. He beat several small welters/ Jr Welters, including Monroe Brooks in 1978. In 1979 he beat full welters including former WW Champion Carlos Palomino. In early 1980, he crushed a totally inexperience light-weight Wellington Wheatley (for some unknown reason), as a final tuneup before the SRL fight in June 1980. That total transition took 2-1/2 years to the SRL fight. Some people (including SRL & Angie Dundee) thought Duran was too small for SRL. Obviously Mikey Garcia should have looked more closely at "The Duran Plan".
I dont think mikey's style is suited for moving up in weight like that. The likes of Duran and pac are different animals. If you are smaller I feel you need to overpower your opponent