It's a ringing endorsement but the subtext is also clear: these were things he had to work on and improve and the things the coaches would look at because they were deficiencies.
MSL's totally right, for a young d-man play without the puck is much more important than play with the puck in evaluating their NHL-readiness. If "JB" is up to speed and broke through his hesitancy to play physical and athletic hockey, he's going to have gained a lot of goodwill and NHL TOI. This is his year.
Barron looked good at the start of last year. He started to become less efficient as the season went and that is why he was sent to Laval. He struggled initially there (as is expected from players who are sent down), but he found his groove eventually.
This year, with him no longer being waiver eligible, he will surely get a better opportunity. If he can slowly put it together at the NHL level, Montreal will be all the better for it. Because offensively. he will contribute. He had 7 goals in 48 games last year. At that pace, he'd have 12 goals in 82. Matheson had the most among the D with 11.
We also tend to forget in his case, he is only 22 (will be 23 in November). He needs to take the next step and be a full-time NHL'er, but it's not like he's been in the pros for like 5 or 6 years already and he is what he is.