I was bored today and decided to look at the number of guilds that have cleared H Throne of Thunder up through H Lei Shen since it was released 11 months ago. Sadly WORLDWIDE it's only about 3200 guilds, including both 10 and 25 man guilds. Doing the math, and adding another 10-15k from PUGs that's only 50k players who have cleared the raid, or 0.6% of the 7.8 million current subscribers.
They've already combined 10 and 25 man next expansion into mythic 20-man, as the amount of resources it took to balance/design fights for both 10 and 25 man appears to have been not worth the cost. My questions is, with burnout, what seems to be a smaller recruitment pool, etc. does anyone think there will be a point 2-3 expansions down the road where Blizzard decides that the time spent on bonus bosses/mechanics/phases for heroic modes is no longer worth pleasing 10-20k people when they better focus their resources on Normal/Flex/LFR and please the vast majority of the raiding subscribers?