[morzh]

Well, by Ron's own words:

"Philco, most likely, switched to the large/medium/small rosette configuration in later production of 70 cathedrals, Bulletins 57-A and 57-B to the contrary."

So, even though contrary to its own documents, Philco might have been using 90- like knobs configuration at some point, which justifies Steve's coniguration as "one of the valid ones".

Using pure statistcs and probabilities, the fact that there are very few, if any (I have not seen any) 90s cathedrals with other than large+medium+small rosettes configuration, and there are quite a few of 70s cathedrals with both "70" and "90" configurations, tells me it is more likely than not that some of those 70s came out of the factory this way.

My layman's two cents.