Mr. A
Let's not get personal, but.......!
I have worked for various airlines where the attitude in rostering was this:
"You are entitled to 8 days off in 28, so that's all you're going to get. Now, how can we fill the other 20 days with duty."
This attitude leads to inefficient use of resources; i.e. rubbish rosters.
Why not roster the productivity, then when it's been worked the rest of the time is free. I know of pilots who have worked their limits in less than 28 days or 1 year, and then been rostered in the office because they can not have extra days off. Mad!!
The limits become the norms. Everything is to maximums and minimums. We work shifts to a random pattern. Why should we work 6 or 7 days censectutively just because it is the legal maximum. No other shift workers work 6 or 7 days; likely not even 5. The Ryanair roster is not good, it's just better than most. Do not use that as a yard stick. On the continent it is common to work 4 & 3, or 6 & 4, but within the 6 there will be 2 SBY's. Productivity is sufficient and there is chance of a social life.
To roster as per my example is stupid and unecessary. At the end of 6 days you are tired and the duty so quoted is the most tiring of the lot. Thus, at a time (landing)when you should be your most sharp, you are your most below par.
Why is it necessary to work blocks of 6 days/nights? It is not. Simple.