The fabulous five best anime are so long that they are equal in length to ranks 6-41 of all good anime, or ranks 42-96, or ranks 97-156. The length breakdown looks like this then:
1/4 = 5 shows.
1/4 = 36 shows.
1/4 = 55 shows.
1/4 = 60 shows.
Just by watching the top five anime in full, you'll end up watching 1/4 of all the good anime existent. If you watch the top 41 anime in full, you'll end up watching 50% of all good anime. This goes to show that the task of watching 156 ranked anime series is less daunting than it initially seems. 1/4 of the way into your rankings, you're already over 1/2 done. Another way of looking at this system is that you could watch the majority of good anime series while avoiding the majority of anime's total content just by avoiding any series of length beyond whatever amount makes you leery. If you go after a bunch of short OAV's, movies, and one cour tv season anime franchises, you could end up with a massive haul of ranked series while never investing much time into the pursuit at all.
This isn't actually a good idea, because you'll miss out on all the best series, but as an undaunting beginning point I suppose just as well as any other starting position.
Let's imagine that the quality of anime gradually grows lower the deeper into my rankings I go. In that case, the first 'quarter' by length gets 4 points, the second 'quarter' gets 3, the third 'quarter' gets 2 and the final 'quarter' gets 1 point. In that case, if you watch just the top five anime in your lifetime, you get 4 points out of the total 10, or you've already absorbed 40% of all feel-good points from anime. If you extend that range to include the top 41 shows, you've already absorbed 70% of all feel-good points. If you go the distance and watch the remaining half of good anime, you'll gain a paltry additional 30% in feel-good points. This implies people really should start at #1 and work their way down.
Another interesting aspect of these quadrants of anime is which ones are still growing compared to the others. The first quarter, composed of series 1-5, is still growing at a 100% rate. That's pretty phenomenal, and a good portion of the reason why they're ranked 1-5. Their ranks take into account not only what has aired, but what will air in the future as well.
What about the next three quarters?
6-41 have a continuing growth rate of: 28%
42-96 have a continuing growth rate of: 16%
97-156 have a continuing growth rate of: 25%
This makes a lot of sense. If you're continuing because you're a good series, you're likely to be in the 6-41 group. If you're continuing because your series has just begun and is thus too short to be rated well, you'd end up in the lowest quartile of rankings. Meanwhile, series that have played out but still weren't that great would end up in the third quartile, which means they're unlikely to receive any sequels that would contribute to their further growth. But the most impressive feature about these numbers is how far all three quadrants fall short of 1-5's 100%. The best shows are clearly the most popular, which is why they have the highest longevity on screen, which goes on to reinforce their status as the best. The facts all fit together.
Meanwhile, having despaired of ever getting an animated sequel to Maria-sama ga Miteru, I've taken to reading the light novels instead. 'A Crown of Roses' was spectacular, the climax of the best part of the series so far, Yumi and Touko becoming souers. The other novels I've read so far have largely been a waste of time but at least aren't distasteful. This reminds me of my experience with 12 Kingdoms light novels -- 'Aspiring Wings' was better than anything in the anime, but the rest were nothing special, nor were they especially bad. It appears that if you venture into the world of light novels, you're likely to find one crown jewel and a bunch of burnable coal -- like Mother's Rosario in SAO, which dwarfs everything before or after and is the purpose of reading on beyond the anime in this series.