I really like Hockey-Graph's article by
Connor Jungle on an
Applied Prospect PipeLinE (APPLE). The math is pretty heavy and I'd do an awful job at trying to explain it in layman's terms, but what it does well is address a few questions like: How likely is a player to make the NHL today?; How much do we expect them to score in the NHL at age X?; What is the development path that maximizes a player’s likelihood to play in the NHL?; What is the development path that maximizes a player’s production in the NHL?
Applying it in Kristian Vesalainen's case, here's what we see:
APPLE sees Vesalainen at age 22 as a 75% chance of staying in the AHL next year, or a 25% chance of making it to the NHL. If he stays in the AHL, he's expected to score around 58 points, whereas being in the NHL he might score as high as 35 (if he plays a full 82 games, not less than 9 minutes a game, etc. etc.). Here's where things get interesting: if you have Vesalainen stay in the AHL for another year, his chances of making it to the NHL the year after is still less than 50%, where even if he was "forced" he would only be expected to score 40 points. However, if he were to play in the NHL for the majority of his age 22 season, APPLE doesn't expect him to drop back down to the AHL at all, and would be expected to score ~48 points instead (again, assuming a lot of optimal factors here).
So, his most likely development path is still AHL to AHL to AHL. But putting him in the NHL next year could essentially make him an NHL regular, instead of a busted prospect that never even got the chance (unless it was in call-ups).
As I mentioned on my Twitter earlier today, there's conversation abound that Vesalainen essentially had to re-create his game when coming from overseas. But I think you gotta roll with him as a regular in 2020-21, bouncing between the 3rd and 4th line at the very least. Give a Lowry-led 3rd line a bit more leash in the offensive zone and pair him with Vesalainen in a shooter mentality (and also give him PP2 minutes), and I think that's your best path for "graduating" Vesalainen from a prospect to an NHL player. Playing in the AHL for another season won't do much for him, in my opinion; much like it wasn't going to do anything for Kyle Connor who went down in 2017-18 and only got called back up (and stayed) due to Perreault's injury early in the season.