The rule is that no SINGLE airline can supply more than 200%. It's also average for the week (since demand fluctuates), so a singular day can be a bit over with no problems as long as other days were a bit under. One must also consider demand on the return trip as well, (as pictures in the 2nd post), as it's not always the same and can skew things a bit, as it quite evident here.
In this case, on the IAD-IST route, there are 3 airlines on that route, EACH is allowed to supply up to 200% demand, meaning that there could be up to 600% demand supplied (if each hit their max allowed) before there'd be a problem.
In both the first post and the 2nd post, there are no rules broken.
In the 3rd post however, Landmark is clearly WAY oversupplying that route and if you want it fixed you need to report it to sami.