one dot right,
the effect is there. The question is on what engines it will be noticeable. All of them? I think not. But on some engines? Weeeeeell... I wouldn't know.
If someone who claims to have extensive experience of operating the Twadoddle PXF38 radially indisposed contraindicating aircraft powerplant says it will show a MAP drop, I'll check on other references to see if that individual is someone I'd generally trust to be correct - until I get the chance to run a Twadoddle PXF38 radially indisposed contraindicating aircraft powerplant in a test bench, or find hard evidence from such bench tests.
In short, I'm only convinced that it will be noticeable as far as my trust in those saying it will goes. I will however not say they are wrong as it can't be - as some people are doing.
If we had several people having operated the Twadoddle, some saying it will show, some saying it won't, then it gets tricky for real - but that does not seem to be the case here. Unless I missed something we have Twadoddle PXF38 flyers saying it will show, and we have people saying it won't based on academical merit (wrong!) or based upon experience of the PXF33.5.