That is all reference frame.
A good player with a long term contract is better than a player with one year remaining on their contract. Given there’s no additional value of sign and trade in the NHL like there is in the NBA, this basically means they traded a player with a long term contract. For that, yes, his value was higher.
But also he used his willingness to do a sign and trade to create said virtual NTC. If he short-lists teams, that handicaps Calgary to either trade him as though he didn’t have the long term contract, or be forced to trade to a small subset of teams. My reference frame is that they would not have traded Tkachuck until the deadline if they could not get a dance partner on Tkachuck’s list. With that being said, limited trading partners add leverage to the other side.
The summation of the value of Huberdeau + Weegar to contending teams at the deadline,at the time, were reasonably Huberdeau = 2x 1sts, 2nd or 3rd, mid-to-top prospect, and Weegar = 1st, mid prospect. If any player could possibly fetch 4 1st round picks, a 2nd or 3rd, and two upper prospects, I think we would see more offer sheets more frequently (for context, max compensation is 4 1sts). Given that Tkachuck was willing to sign long term, I would equate that fact to be balancing out the equivalent of acquiring a player of his caliber with multiple remaining RFA years.
In my mind, there are very few exceptions to that max value designation. Those are players whose value break the system and the salary cap makes their individual value fuzzy. Connor McDavid, for example, is individually worth more than the maximum contract value, and would be worth more than 4 1sts (under the assumption that he’s refusing to sign). I’m not really sure there are many (or any) other players who meet that criteria though, and I don’t believe Tkachuck does.
Also as some of you may have noticed, my phone autocorrect’s Tkachuk to Tkachuck. I hate it but I gave up a long time ago. I probably wrote it once and it has forsaken me since.