Interesting this theory about only running in engines on crappy standard type oil. Advice I got from the customer service at Opti-2 to use it from day one just take it a bit easy, and Opti-2 is as good for new engines as it is for old.
I am yet to read anything that would sudgest not to run in a motor on a synthetic oil. Mind u Opti-2 is not a synthetic oil at all, its parafin based. See linky Which 2-cycle oil for Toro snow blower.
I have used this Opti-2 stuff in all my 2 stroke mowers and edges from new for years with no problems.