Trondsi this statement is a decent indicator that your test is not just flawed, but that something other than pushing gave you that difference.
Pushing (extra development) simply can't "fix" an underexposure.
As camera exposure is reduced more and more, more and more of the darker details in the scene are excluded. The silver in any given film simply has to get hit by enough photons or it won't develop no matter how hard you push it.
Last edited by a moderator: