The calculation isn't wrong.
There's 2 things at play. One is your math, which seems to assume that it's a given that salary must be allocated in a certain way to fill certain roster spots (2.5-3.6 for middle 6 F, 2-2.5 for 3Ld, etc.). What I posted was just how it would have been possible to ice a roster with Buch in that year.
Attached is a rough side by side of actual cap allocation for those 4 spots vs a Buch version.
That's all kind of besides the point, though. The real issue at hand is that there's no law that stipulates that certain amounts must be allocated to certain roster spots. Whether the Rangers necessarily operate that way is a different story.
What i'm trying to express vis-a-vis the Buch salary cap issue is that the way a team *should* be run is to prioritize signing top talent, and then fitting everyone else around that. If that means 4/6 bottom 6 spots are ELCs or minimum deals, so be it. You can find minimum deal guys who can contribute grit, depth scoring, PK, and locker room intangibles - they're available every year.
Buch was not identified as a necessary puzzle piece around which the rest of the roster should have been squeezed. That was the primary error. If you assume as I do that the optimal roster construction included Buchnevich, then the math would have worked. Trocheck too.
As far as
@Machinehead's contention that (terrible return aside) trading Buch has been vindicated in some way by Zibanejad/Kreider's decline since 2021, I've made it clear that it's not just the performance of *that line* that retaining Buch would have affected. It's the perennial outflow of value from NYR coffers to the rest of the league to fill the spot that he left.
Machinehead and Barnaby and everyone else want to blame Kakko for not being the player they expected him to be, not being the player that was deserving of the red carpet they laid out for him. That's bullshit. the player has been disappointing but has been positive value based on cap allocation.
Let it be a f***ing lesson to NYR - don't trade your top line wing for unproven prospect, regardless of pedigree. Definitely don't do it for Sammy f***ing Blais...