I don't think that is always necessary to go to extremes, but sometimes it may be. I have been there and time off does help, but not always needed.
Syptom:
Take off a few days feel fresh then get back to "normal pace" and in a few days -horrible.
Opinion:
It may be the "normal" pace may need to be adjusted for a while. Even a reduction in mileage won't always get you back to adaption potential.
Personal example and remedy:
Months before-
Steady improvement in performance and volume. runs at 6:30-6:20 in between
1 Monday beginning of the month ( Tempo 5:10 pace, 1000s in 3 minutes)
-- Runs in between at 6:20s
2. Monday end of the month ( Tempo 5:20 pace- Same effort or greater, 1000s in 3:08 and then I bag the workout because I'm disgusted and depressed.
I take 3 days off get back to run a run at 6:20 pace and feel great. Do this for 2 more days and try to pick it up but feel awful.
What to do?
I adjust the intensity of my "easy runs" and my workouts.
So I take 2 or 3 days off, jog 2 or 3 days, then do my 1000s in ridiculously easy paces. ( 3:30 rather than 3:00). )Tempo in 5:50 pace rather than 5:10 pace) . I run ridiculously easy for my in between runs- 7:30-8:00 minutes vs 6:20s.
I do this gradually increasing the tempo and intensity. After a while my body "catches up" and I revert back to where I was and then improve from there.
Now this depends on where I am in the season.
Another example:
I ran a very hard track season and now I'm dead,( June or July) but still want to use my fitness to prove myself in road races. Considering I am interested in cross later( Oct, Nov)
I decide perhaps it may be a good idea to go up hiking and forget about running for a while. ( August 1-15) Now I slowly get back to it Aug 16 until I peak in 6-12 weeks later.
So that's my idea for what it's worth.