Bob:
I can't answer your question - different manufacturers did different things. I can tell you that by the mid-1960s, the two-large/two-small burner configuration was seen on TOL and then upper-MOL electric ranges. However, the three-small/one-large configuration continued on for decades on BOL and lower-MOL units.
I personally find the lack of a second large burner to be a deal-breaker. The only time I've ever considered doing without one was when a Spacemaker 30 like the one shown in the photo I posted came up for sale here in Waterloo. That is such a rare and beautiful range that I would have tried to deal with the lack of a second large burner.