Agreed. With a SF Tibetan pair, The good old Punnett square projects that 75% would be Tibetan (SF and DF), and the other 25% would/SHOULD be wild type Coturnix.
....of course things don't often come out EXACTLY as expected, but that's part of the fun with genetics.
I have a gouldian pair both spilt for blue. Technically 1 out of 4 chicks SHOULD be visual Blue...40 chicks and I finally got ONE! Not Quail... but genetics nonetheless.