You could be right too Old Soyko. I have related what I have heard any number of times. But that doesn't mean it's right.
I do know, as Dale related, that Cherry Tomatoes will produce like crazy, just from the small tomato seeds left in your garden over winter. As a matter of fact, I just found two Grape Tomato Plants growing in my garder that I didn't plant.
Years ago I did try saving seeds from Big Boys and Beefsteak, with no luck at all. The plants were small and scrawny and never bloomed nor produced. Maybe cross bred is different than Genetically altered, which I am sure the Pink and White tomato's are.
I suppose it will be a trail and error exercise. Dale can fill us in on what works.