the answer was no seperate circuits and the need was not absolute so in this case multiple lights(on each side) would be wired parallel on each respective side...
I do not see where these fact's are confirmed, did WB contact you by PM?
The relay wiring would seperate the functions for the trailer if thats what woodbutcher wants to do.
And I really enjoyed working out a solution anyway, I enjoy doing IQ tests and logic puzzles.