(warning: long essay - only the first paragraph is really a response to you,
@KFnC204 - but then it got my brain thinking about this whole thread, and I decided to outline my perception of our current context since I haven't chimed in on this thread. Apologies for long-windedness in advance!)
Some people use historical data, evaluate what could have been improved based on hindsight, and then make better decisions in the present. Other people are doomed to repeat past mistakes if they haven't understood what went wrong.
In Petan's case, it is an oversimplification to say he was too small, not tough enough, etc - those things were sort of true, but not the whole picture. Evaluating what actually happened on the ice, we could see that there was a situation in which Petan excelled. However, that situation did not fit into Maurice's preconceived notions of his deployment strategy. Instead of changing to a top 9/bottom 3 approach (once or twice we had the personnel to do it, but he never tried), he stuck with his top 6/checking/scrubs deployment, and Petan (as a playmaker) absolutely sucked.
(there were also non-hockey factors that disrupted Petan's development at key times, like losing his dad... Hard to quantify that effect).
The org made the correct decision to cut him loose because they chose not to change their deployment strategy. Personally, I'm more a fan of evaluating what pieces you actually have, and then finding a way to maximize their talents. Maurice was not capable of that, it requires cognitive functions that most extraverted former players have as blind spots (because you have to be awesome in the moment to make it as a player).
Why does this matter? Well, in this thread, some of us are seeing a similar trend - one option is to not play Heinola and disrupt development (and its bullshit to say that the NHL is not a development league - every player keeps developing or ends their career: just heard Jagr say in an interview about how he continually was learning to adjust his game to his abilities). The other option is to reevaluate deployment.
The tricky thing with Heinola is we're dealing with contract status (waiver exemption) and some handedness issues, and only one spot. What coaches struggle to grasp (yes, even some NHL coaches) is that to achieve maximum potential you have to sacrifice some present results (and we're only talking short term: like suffer for 2 weeks and reap the bonus benefits for an extra 6-24 months).
Things also changed for me when we signed Dillon and Schmidt. I was 100% in favour of playing Heinola instead of Beaulieu or Poolman or Bitetto or Sbisa. But Dillon is probably the best 3rd pairing quality D we've had and Schmidt is getting paid a tonne to be just a little bit better than Heinola (but I think Schmidt's good enough to not benefit from the short term sacrifices we'd have to make to play Heinola fulltime). So that puts us in an awkward spot.
So, just like we should have either changed our deployment or traded Petan, I'd like to see us get something for our assets. Getting Schmidt in particular basically made Heinola redundant - so in my eyes one of them should be traded, or we get nothing for H's 1st round pick.
In hindsight, it's clear Chevy was going all out to win last year, to please Maurice got semi-established D's, and the team crashed. It would have been better to play Heinola fulltime and rotate Samberg & Stanley last year - we would have had the same result or a better draft pick, and we'd be miles ahead right now.
Personally, I think we should always have one or two rookies playing to constantly refresh our team - but again, what we learned from Petan, that requires an intentional deployment taking into account our actual roster instead of a cookie-cutter template that worked in the 80's.