I've been wondering the same thing, but I don't have a Duomid to experiment with. I had pythagorized the same 66" (65.299 rounded up), but most of my poles are fixed length at 115cm (45 in.) and would therefore be impractical, unless strapped together in sets of two, which would require a non-solo use of the tent ;).
Nonetheless, I'm curious to hear other peoples ideas on the strength benefit this could/should/would/did provide. I imagine that for exposed + snow use, a setup like this could be of great benefit.