Once you've nailed down your base exposures midtones can be adjusted by dodging during either the 0 or 5 exposures and then burning in with 0 or 5 later on. I've found it an incredibly precise way of controlling all aspects of a print, including midtones. Simply a different way of getting there.
Same here with a couple examples. The midtones were extremely important on both, but the lows and highs tended to dominate. This one was taken on TMY-2 and was a very dense contrasty negative. This one was taken on Type 55 with more conventional contrast and density.
I don't use split grade filtering exclusively but its certainly an important technique that I use frequently when the situation warrants.