The last L85 sheet I uploaded was here:
Summing up. Here is, I think, the optimal socketing flowchart.
Assuming blue gems are better than yellow (i.e. Spirit is worth more than haste, and the hit cap is not a problem):
1) Let N be the total number of sockets you have. Let R be min (number of red+prismatic sockets,(N-1)/2).
2) Put R red gems into red/prismatic sockets.
3) If there are still red/prismatic sockets left over, put purple in them.
4) Let Y be min(R, number of yellow sockets).
5) Put Y green gems into yellow sockets.
6) Put R-Y blue gems into blue sockets. //you're now at red/blue parity and have at least one blue or yellow socket left.
7) Put one blue or green gem into one socket. Meta requirement now satisfied.
8) For each remaining pair of blue/yellow sockets, socket one blue and one orange gem.
9) If yellow are left, fill with half green and half orange. If blue are left, fill with purple.
Hmm, this came out worse than I thought. I'm going to see if I can clean that up into simple rules. And this isn't even getting to the possibility of ignoring socket bonuses.
EDIT: the above isn't totally correct. I'll try to make a good writeup.
Forgive me for my ignorance, but how does the accounting work for the meta requirement? Specifically, does it take two greens to equal one red (i.e. two half blues required to offset the whole red), or does a green count as a full blue gem and a full yellow gem, and thus a purple equal a full blue and full red that offset one another (which is the same as the current wrath model)? From reading this, it seems as though it's the latter indicating no change from the current regime, in which case I think your guide is, indeed, completely correct.
For clarity, I may combine step #3, #8, and #9 into a final catch-all step: "All remaining red fill with purple. All remaining blue slots fill with purple unless there are remaining yellow slots. For each empty yellow slot that has an empty blue slot available, socket one blue and one orange gem. For each pair of empty yellow slots, socket one orange and one green. For a single yellow, fill with green."