38 pages and counting ...
I really don't think judging results based on 1 summer is really wise in case of a young player, who also probably is lacking behind in some aspects of his physicality - I'm basing this on my gut feeling and some comments made by people who know better than me. Also time for bulking up is absolutely now that his body still takes on muscle very easily. He is 6'5", Lemieux and Lindros were an inch shorter and I think weighed around 230lb and 240lb... while Laine was maybe 220lb last season?
Yes, the game is different now, but a young player can afford to carry a lot of muscle if it's in the right places and they'll be stronger for it. Also it seems some people think all carrying more weight/muscle does is make him slower, but have you thought about what kind of beast a ~230lb Laine could be with the puck and in board battles?
Currently he is definitely underperforming by the boards compared to his size, but I think that's because of lack of strength and core. I have a feeling there are many areas where his physical training has lacked in his younger years compared to some others, in juniors he probably got along just fine with his size alone + it seems he really had some attitude problems some years back. In contrast I've always been amazed at how strong Sebastian Aho is on the puck, despite being a lot lighter and way more lanky looking than Laine. I always figured it was just because he's always been on the small side and had to learn how to compensate for that with technique, but then I read some article sometime ago and apparently he was always a heavy trainer and has some sort of background in gymnastics, which would be great for both core strength and agility/coordination, and it started to make sense.
Laine on the other hand is for the first time facing a situation where he doesn't have physical advantage to his peers (at least for now).
I find it also a bit funny how many people remember his rookie season through rose colored glasses and remark on how much better he looked back then than his 2nd season. I call bullshit on that, and there was A LOT of talk during his rookie season on how he looked like a bambi on a skates etc. Also he was a lot more inconsistent, during his rookie season there were many games where he absolutely LOOKED like he didn't belong in the NHL at all. Then he'd score a hat trick, sometimes in the very same game... History gives perspective on things, about this season people won't be remembering his "poor skating" and poor first steps, but the 44 goals and 70+ points and coming 2nd to Ovechkin in the race for Rocket.
I don't think random people on a hockey forum can have any sort of idea what kind of training he should be doing or accurately judge the results he is getting. After all, all we see is what happens on ice and what we *think* is the problem, while Laine and the people coaching him in his training will know exactly what is going on with him physically, his test results etc. etc. and if they are competent, should be able to come up with a long term training plan which works and also be able to adjust it as needed. And I believe in Laine's case it really is a long term plan what is needed. That doesn't mean people shouldn't expect improvement season to season, just that the full benefit is longer in the works.
I haven't done this, but I bet if you watch Laine rookie season games vs. Laine sophomore season games side-by-side, the second season Laine is a way more balanced and consistent player, physically as well. The better 5v5 production as a rookie was more about the whole Jets playsystem + playing with Scheifele instead of Little.