This is interesting indeed.
I have "bounced back" from many relapses, some pretty severe, and have surprised everyone.
When I'm in the gym and forced to do certain exercises that force me to rely on muscles soley in legs, then I shock everyone with my weakness.
It seems I am swimming using only my arms, despite legs thrashing around they are actually propelling me backwards.
And I've an incredibly strong core muscle set, due to years of digging on archaeological digs from 15-25 years, then cycling, tai chi, yoga, aikido etc. Despite not being in shape now, my core muscles are compensating for loss of power to leg and arm on right side, so I totally agree with this neuro-physio. Spot on!