Progressing MC with True Solar Arc in Longitude

Hi,

I'm an European astrologer and like to learn more about the Secondary Progression method with progressing the MC in longitude that I suppose is popular in America.

Where I come from we almost exclusively progress the MC on the equator in right ascension.

Lately I read two books about Secondary Progressions from the American astrologers Sophia Mason and Zipporah Pottenger. They are progressing the MC with true solar arc in longitude. That aroused my interest to learn more about this method that's new to me.

But in Europe it's hard to find somebody who got practical knowledge with this method. Because of that I'm here to hopefully find some answers to the questions that interest me.

So if one of you can answer one of the following questions about progressing the MC with true solar arc in longitude it would help me a lot.

1. Is it true that many North American astrologers are using this method today?
2. From the American astrologers who work with Secondary Progressions how many of them are using this method in percent approximately?
2. Who was the inventor of this method in the past?
3. In practice do you think progressing the MC in longitude leads to more accurate results than progressing it in right ascension?

Best Regards,
Chris

I wonder why I didn't get any reply. Am I in a wrong forum section or section that nobody reads?

Or is my assumption wrong that Secondary Progressions with MC progression with true solar arc in longitude is used by many American astrologers?

I have the impression that European astrologers are more cohesive and organized than American astrologers. I just assumed it was done with longitude, and I'm glad you asked the question, even though I can't properly answer it. I have a question for you: Is there a general consensus in Europe regarding House systems?