This is a good mm. While I think Stevie would be a clear favorite over Danny Garcia, Amir has all kinds of advantages over Johnston and should be favored. Johnston doesn't hit hard enough or pressure enough to catch Khan and he'd lose more rounds than he'd win.
Well, prime Stevie was a lot better than Kotelnik, Paulie, and washed up Judah. He was a much better skilled operator than Peterson as well. He had enough quickness, and skill to get inside on Khan's sloppy ass, and basically beat him up. Khan would win some rounds, I admit. But in the end I think Johnston beats him clearly. Generally I find Stevie Johnston to be overrated. However, Khan is quite possibly the most overrated fighter of the last 25 years.
Whilst this is true, it's irrelevant as Khan won these fights with ease and was never troubled. Saying that, Khan was really bad at lightweight, if Willie Limmond could nearly have him out of there then I have no doubt Johnston could do it too, despite being a relatively light hitter
Sure stylewise it's not a bad fight for Khan, but Johnston is simply a much superior boxer and it would show.
There are a few imponderables, such as Stevie's stance and facial swellings, as well as out-of-the-ring preoccupations, but as a general rule, Khan does better versus non punchers than he does vs bangers. Stevie was a competent guy but he's small. When he fought Billy Schwer, he didn't do a whole load other than outbox his man, and never came close to stopping a guy who bled profusely all night from the cuts he had always suffered from in his career. My gut feeling is that Khan, who would be much bigger at the weight, does enough to stay out of grief and outpoint his man. Stevie would have to step in and land something really big, the thing is he wasn't the sort of guy who did that. Against Cesar Bazan we saw Stevie struggle with a taller opponent who was himself subsequently blown out by Castillo. When he fought Castillo, Stevie showed good skills but again the size difference told. Khan is a big 140lbr, he was a huge 135lbr.