There are very easy ways to confirm your beliefs. That's all they are right now is your personal suspicions that you are pretending there is data to support.
The ECU did not "learn" your way into 15ph. The IAT and the MAF and the MAP are what they are. If you reduce restriction then you see the immediate change in the MAF. If you don't 'like' or 'trust' the charts provided by GRP who did testing for everyone, then grab another intake and do your own. The blue replacement filter is an easy option. It's possible that the GRP testing proved is that at 3,000 ft above sea level there is not much difference between filters. Or that the dyno he was using has a high level of variance that averages out to minimal differences between options. No one can really say. BUT what no one should be claiming is that there is some "magic" which invalidates his testing and dyno over your own results.
If I cared enough I technically have both GRP and Eventuri and i still have my stock one sitting around, I *could* do this testing, but I don't care. Critically though, I am also not the one claiming that Greg or his methods are wrong.
Even easier for you, would have been to prove that the Map0 (no JB4) to Map 1 or 2 was a meaningful change. Two different days running a dyno will result in different readings. It just is the facts.
It's nice to believe that you can regularly prove the incremental improvements you are making from a Day 0 dyno. But the fact is the conditions of that Day 0 dyno are never perfectly repeatable. So you could gain/lose 5hp just because it was a bit misty that morning. Just like with track times posted by magazine/reviewers, anyone with sufficient experience knows there are only generalizations. You cannot truly compare 2 lap times from two separate days and 2 separate conditions.
You regularly make claims that cannot be validated by anyone else, and speak loudly as if they must be true. When people ask you why you don't show the sort of 'rigor' your posts indicate that you care about, in order to validate these claims you offer weak excuses like "I know what stock is like I don't need to do a Map 0 run". Do you think its a coincidence so many people asked this simple question? Do you think everyone who did had no rational basis for the logic?