Mr. Angry,
A pleasure to hear from you again on this subject. It was a couple of years ago, when threads about pilot workload and its affects first brought us together.
In answer to you saying that you know of no pilots who do 4 On 4 Off. and therefore imply it is impossible. Why not? Its not having been done before does not make it a bad idea. All I'm saying is that it is very common for shift workers, including those on the ground within airlines, and does not seem to cause the knackering effects of a normal aircrew roster. (I stand to be corrected).
Nobody should be tired (and never fatigued) on a regular basis when doing a normal job, especially one where a lapse of concentration can have calamitous consequences. Of course there is a difference between tiredness & fatigue, but it should not be the norm. This is the 21st century and the EU workers directives have improved things for most workers, execpt in public transport. I sympathise that you are tired with 1 day off in 14. I would be too, and it is not reasonable that you should work so, but it is irrelevent to the discussion. It smacks of the old worn out response from the senior pilots when young F/O's winged about this or that; "Don't worry son. Just put up with it and your time will come. I did it, so you have to."
Just because one person in the team has a rough time of it, is not a reason not to allow improvements in another link in the chain. By raising standards in one area it should help lift standards in all others. Level up not not down!