You're right BIK. It is an international requiremetn. But at the end of the day an appropriately trained and qualified person, who may be a pilot, must be trained to the same level of competency as...you guessed it, a LAME. If that person is you then congratulations, you've successfully mastered two of the most demanding technical occupations in Aviation. If not, then you are not appropriately qualified, whether your Ops Manual or MCM syas so or not! It just means that you probably had our approval issued from CASA Brisbane or Sydney.
ICAO Annex 6 Part 1 Chapter 4 is the reference.
To be clear, I am not talking about the long-range, low-cycle aircraft like B747s and B777s. For those aircraft the sectors are so long, the cycles are so low, and their destination ports are so well served by third-party maintenance organisations that there is no logical reason why you would want to use up a long-haul pilot's valuable duty time performing a pre-departure inspection. Rather, I am speaking about F100s, B737s, BAe 146s and similar.
This statement simply illustrates your ignorance for one, of the effect that high cycles have on an airframe, and two that your argument is based purely on cost.
It is the understandable ignorance that you are exhibiting that is contributing to a less safe RPT environment.