Hi Bloke,
you have made a pickle of a problem.
We can't be 100% sure that Buddy's SC fate is Tippett related, but there is strong evidence there.
I guess your decision comes down to, who do you have less faith in?
Petrie - has he turned the corner?
Buddy - does he need to hunt the ball, rather than be the main hit up man?
Cotchin - is he hampered beyond repair, and will be lucky to score over 100/game from here?
Let's assume if you trade one of those 3 out this week, that semi-disaster strikes, and you are stuck with the other 2 for the rest of the season. Under those circumstances, you'd probably keep Cotchin even though we are expecting restricted return from him, from here. So it comes down to can Buddy shoulder the load, or can Petrie cash in on his easy draw? Given Petries score largely came in one quarter last week, I'd be tempted to choose Buddy over Petrie.
The other way to look at it, is what will cause you more frustration? Changing your plans, and keeping Petrie on the back of one good quarter, and then seeing him cough up 60's and 70's again? Or trading Petrie out, only to see him out perform Buddy, who you suspected might drop off a bit without Tippett there?
If in doubt, it means there isn't strong evidence to change your mind. That means your original plan is probably best.
Good luck