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"A larger MAB will start the mains SOONER"

"A smaller MAB will DELAY the start of the mains"

I have seen this posted by some and I have seen the opposite posted by others. Both sides quote books written by experts.

I thought it could be tested and I would know first hand which side was right. The test I did initially was with no load on the engine and changing the main air bleed size and observing at what rpm the mains start flowing fuel. The results I saw were that the mains start flowing at the same rpm regardless of main air bleed size. (This test could be done by anyone with a carburetor that has adjustable main air bleeds, an assortment of bleeds and a tachometer to measure rpm. I would everyone to not take my word for the test that I did and try it themselves. Maybe you will have different results.)

After seeing no change with no load I thought, "maybe it will behave differently with a load on it." Luckily the motor was on the dyno so I could put a measured load on it and observe the rpm that the mains start flowing fuel. I tried it at two different loads. What I estimated as the lower and upper end of the load that would be associated with cruising at highway speed ish. Having a load on the engine resulted in a change at what rpm the mains started flowing fuel but when the main air bleeds were changed the rpm that the mains started flowing at with that load remained the same.

Why? I don't know. It is even possible that test I did ( while remaining consistent with the results) is somehow flawed.

Is there anyone else out there willing to try this test? Even the test without the load?