Instead of coming up with other researches, why not debunk the one I posted the link to? I am very familiar with Toole's work and his views regarding this matter, thanks.This is from (Amazon's preview of) Dr. Toole's book Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms.
He measured the frequency responses of the whole loudspeaker (not just driver) and conducted listening tests. There were measurable differences in the woofer compliance—no surprise here. Changes in the FR were minimal, and the listening tests showed no audible differences. You don't have to take his words for it, you are welcome to conduct your own tests.