You may be right, but personally, have a hard time buying an mcl remains an issue. Everyone is different and any injury is unique…but my anecdotal references personally and teammates were always pretty simple and quick recoveries with the exception of acl/mcl together.
I could see it delaying his summer workout routine a bit, and that can have you feeling behind the 8 ball, but it’s only limiting per se in that you probably can’t improve your skating much - but you shouldn’t have any issue catching up to where you had been.
Maybe it’s a bit more complicated and is lingering. Maybe it’s a mental thing rather than physical. I think it’s a small part of both, but the biggest reason he’s looked like a distant 6 at 4 nations has nothing to do with him being off…it’s how much higher the pace is there.
Im not sure how much he can improve as a skater at this point, but i would agree he needs a full, healthy summer working at it to make any noticeable progress