To put things into prospective the US Air Mail pilots in the late 1920s were required to have at least 500 hours of flight time to fly those contracts. Think about that for a second. What was the average lifespan of an Airmail Pilot? That was hard IMC flying with minimal equipment.

I guess my question is why was the commercial requirement ever as low as 250 hours. These airmail pilots weren't even carrying people and they were required to have more experience than today's airline pilots.

Let's look at experience. Air traffic and travel is much different today than it was back then, but I would almost look at the airmail pilots as being the bush pilots of the lower 48. That was experience. Flying around flight instructing, towing banners and and the like doesn't compare to flying single pilot IFR for a small freight company, or flying for a small charter outfit.

I think what the regulators are looking at is that you should be able to trade experience for the Total Hour requirement if the experience is useful and pertains to commercial aviation. (time spent flying a king air or something high performance through weather at altitude in busy airpsace. Not spending 500 hours flying through the same airspace in central FL and never getting any experience with Icing.)