Been a while since I have flown PA34 but could the reduction of rpm to 2500 cause the MP to drop to a suitable climb MP setting like 35".
I know when I first went on the PA34 throttling back would drive me nuts as reducing the rpm caused the MP to drop and needing resetting. (Turbo slowing down).
I know we teach TPM to reduce power but does reducing rpm first to 2500 cause the MP to drop say 35".
If throttle comes back to 35" first, then pitch to 2500 does the MP drop below 35 requiring resetting?
Can't remember since not having taught on them for 15 years since the CAA killed of multi rating to mortal souls.