So a boat in question has the following results from a leakdown test: 2006 525 EFI's, Dart Pro1 heads with around 80 hrs on heads and under 300 hrs. overall.

Port
1 50%
3 10%
5 10%
7 50%
2 65%
4 10%
6 7%
8 11%

Stbd
1 9%
3 5%
5 80%
7 35%
2 11%
4 7%
6 5%
8 10%

Results indicate the boat should barely run. But, in fact it idles fine and runs out very well right up to WOT with no indication of being down on power. What gives? Re-test?

I have seen results like that show up when the tech didn't bump the engine over to close the valve train completely - just stupidity in that circumstance

Firing order 1-8-4-3-6-5-7-2 - on the port engine has #7,#2 and #1 failing miserably which could mean the engine wasn't bumped over or there is serious damage creating the output or as already stated - valve train is out of adjustment.

Did he run a compression test?

My guess is the tool is the Horrible Freight $10 version, guaranteed to produce invalid results.

Quality HP shop with a experienced HP tech. Things can happen even with the best tech, but it just doesn't add up. Compression test was not done.

when was the last time the engine was run before this leakdown test ?

A week or two as I understand it.

And was the engine warmed up before doing the leak down? All it takes is a tiny piece of carbon on the valve.