I'm reaching the limits of my understanding here, but it is the technique they use for the repair. Lots of advancements where the incision is smaller, the risk to surrounding nerves is less (or non-existent), lower risk of infection, the tendon fully heals, the time to recommence loading is a lot less and patients generally report positively as to lingering pain, function and strength etc. Of course, everyone responds differently but from all reports Josh is progressing well.
From my understanding the surgery technique combined with the rehab protocols has come a long way.
There have been a few examples in European Soccer where players have come back after only 7-8 months.
Hopefully Goater has no issues long term.