@slowjet & ironbutt57
I know it's a hard commercial world but...
In a hub & spoke operation of the kind that TK (or the ME3 and many other majors) do, there is no such thing as 'simply shift departure by 2 hours'. Either the flight can be fitted into the connecting banks, in which case it can be operated successfully, otherwise it is commercially not viable. Low-costs are free to shift departure times as they please because they only cater to point-to-point traffic (and to a significant extent this is why they can have a lower cost structure, but in return they also limit their market access).
This being said, in a well-ran outfit scheduling listens to flight-ops and monitors statistics to make sure that the flight can actually be operated in the scheduled timeframe. Many moons ago when I had responsibility for scheduling I had a half-day blocked off each week to take a cockpit ride on one of the problem flights and discuss with crew and experience first hand the issues and possible fixes. In some cases the conclusion was to axe the route after flight ops could not reliably meet commercial requirements.
I visit this forum for the same reason, to listen and to learn. Unfortunately at some outfits (likely including the subject of this thread) this is not in the culture.