That is just wishful thinking, first of all most mythic raiders can't just overcome bosses with their skill alone. Nor they have so much time as people from world first race.
Raid bosses became much more tight since TBC and "standard" raiding hours is like 3x(3-4)h each week.
Gear plays a big role in how timely you can down bosses and you would knew that if you ever discovered kill % vs ilvl statistics on WCL.
Also having vision of 6 month of progress doesn't make you optimistic.