1. in that case why do you want to trade a young controlled future 30 goal scorer?
2. and why should we accept the take of bruins fans on debrusk? did you hold the above negative opinions about the other guys you mention before they were traded, or did you pump their tires hard the same as you are pumping debrusk's tires now?
1. You need to give to get. Debrusk is likely a valuable piece if we want to trade for a better player in a different position. If not, I'm sure many would be happy to keep him as plan B. Take him for what he is, Bruins are either trying to move him for a top 4 defenseman, and/or are trying to sign FA top 6 wingers. We'll see if they are able to do that. As a fan, I'm losing faith in Sweeney's ability to do that, but remaining cautiously optimistic.
2. You don't need to accept anyone's take. The same way no one has to accept yours or mine on any player in the NHL. Every fan base has those that over and under rate their own players. What we say on message boards doesn't affect the actual value when the GM's make the trades, so "pumping tires" as you put, is just to make fan bases feel better about their players or potential ones coming in.
As for the players mentioned, my take for as little or as much you want to from it:
Spooner was very polarizing to the Bruins fanbase. Myself included thought Spooner would eventually usurp Krejci in his role. That obviously didn't happen. He was playing decently before he was traded, the concern was if he'd be able to maintain it. The answer for a very short period of time was yes, and then it was a hard no.
Donato was an NHL ready prospect, but not at the calibre of a cup contending team. Some were sad to see him go, but everyone knew Coyle was a much better fit for the Bruins at the time, because the Bruins couldn't wait to see if Donato found his game. Teams not in as much of a crunch to win, can afford the time to develop his game more. If he does, remains to be seen, but the potential is there.
Heinen, again, polarizing figure on the Bruins. Put up very solid numbers his first full season. He's a jack-of-all-trades, master at none, which more or less didn't make him stick out, but he put up adequate numbers considering his role. Bruins needed more size, and rightfully or wrongfully chose Nick Ritchie as the option with Heinen as the player going out. I still think Heinen is going to have a better career than Nick Ritchie Even though I do think Nick Ritchie will eventually settle in better on the Bruins.