As is common practice last season I had a rest day once a week - that's 6 days on 1 day off. I did find that when I was forced to take extra rest days (kids, work etc) I often got unexpected performance imrovements, but not always.
This season I have long resolved to take more rest days and to eat more. Last time I was so obsessesed with weight loss I forgot to feed the adaptations. So, since August, I have taken a 50/50 split between workouts and rest days (not neccessarily 1 on 1 off, but consecutive workout days are followed more or less by the same number of rest days). I have also eaten whatver I fancied. I don't drink so that isn't a problem for me. As a result, over the last 4 months or so I have made great progress in most of my critical powers. I've only lost a modest amount of weight but have enjoyed being able to ride harder when I do train, and boy have I been riding hard!
As I get stronger the 50/50 split feels too much, I am often raring to go but with a rest day "enforced" on me. So I've moved to a 5 day week. My training is split into "months" of 21 days and I break that down into blocks of 4 training cycles of 5 days each.
Basically, I train for 4 days and then take a day off. four times in a row. I go hard for each cycle. at the end I take a couple or three days off and repeat the process.
No fatigue, high motivation and great leg strength. Will report back in a couple of "weeks" to let you know how this block has gone -- by looking at a full hour FTP test :-)