Yes, if you placed the M3Ti and M22ti side by side, without a sub, you'd notice a subtle--albeit real--difference in midrange and lower midrange clarity because of the M22ti's dual woofers.
The subwoofer handles the low-bass duties below 100 Hz--but there's still all kinds of upper-bass and lower midrange-information from 100 Hz up to 3,700 Hz, which is the frequency that the tweeters in both the M3ti and the M22ti take over.
All the male and female vocal ranges--indeed much of the musical energy for most instruments (except the deepest bass frequencies ) fall in the region between 150 Hz and 3,000 Hz, and that is what the dual woofers in the M22ti and M3ti will continue to handle.
All drivers produce distortion, which increases as the woofers have to "work" harder at moderate to high volumes. The M22ti's twin woofers share the workload even at moderate volume, so distortion would be lower than the M3ti's single woofer. These differences are audible with careful listening even at moderate volumes as an overall "ease" and improved clarity, especially with complex material.
Axiom Resident Expert