Well I'll be darned. Lookie there even Trylon TSF agrees with you in regards to their 25T series and also the STG series.
http://www.trylon.com/lightdutytowers/pdfs/25T Guyed Tower Installation Manual.pdf
http://www.trylon.com/lightdutytowers/pdfs/STG Guyed Tower Installation Manual.pdf
Apparently sometime in the last several years since I left the broadcast business the ice and windloading specs have changed. My hard copy of the Rohn and Trylon specs say a differant story but are about 10 years old.A former collegue in the business,whom I mentioned this to today after seeing your post this morning, told me the specs changed a few years ago.Since it was not practical to change tower design specs the specs on the guying requirements were upgraded to reflect the newer wind/ice loading requirements.This is one time I am glad I was wrong as it lead me to new updated specs.Ultimately the guying distance is not all that critical really and depends on soil conditions. Further distance would be required for sandy or loose soil locations and shorter distances can be used in rocky conditions such as where rock bolts can be used.Either way, 80% or 66% will work fine for any CB or ham tower. The big 500 foot plus towers are a bit pickier when it comes to specs.
...runna pile-up on 6m SSB