There are two issues, bleed pattern and quality of life.
As Sheila said if you have little or no residual ovarian function left you should in theory just bleed when you stop the course of progestogen.
If you are still cycling yourself then this can make things a little more complicated in terms of bleed pattern.
However short term if you have a particular event, work project, holiday etc it is ok to skip the odd course of progestogen, either to feel and function your best or in the hope of avoiding bleeding (although the latter is not necessarily reliable).
Longer term if you want to do long cycle in order to minimise the progestogen burden, even having found the least offensive candidate, which is what I plan to do myself, you would be best to get under the care of a supportive and open minded specialist, and if you can't find someone and end up going it alone, you MUST be really on it with private scans to monitor your endometrial health.
Personally I have the knowledge and confidence to do this safely however it does concern me when others who aren't that lucky are left to fend for themselves and end up running into problems with bleeding and hyperplasia.
Long cycle (5-12 weeks) with a therapeutic dose of estrogen has only ever been successfully accomplished over the long term in significant numbers with synthetic progestins, which are typically given at robust doses for 14 days.
There used to be a commercial preparation called Tridestra which had I think 2 weeks of provera at 20mg every 12 weeks, and there was also one week without estrogen, which I personally would skip if I were doing this.