CMvidini im not quite sure what your getting at here.
When you embark on a 737 TR ,previous experience on other aircraft or "Airline hours" does not come into it , there is "no reduction of hours"
You do what is required of the training syllabus of the TRTO or Airline who is providing the training for the specific aircraft that you are being trained on.
There is no cutting of corners with the hours requirements and rightly so.
The only reduction in hours would be if you were transitioning on the same family of aircraft , ie A320 to A340 or 737 Classic to 737NG, only then would you do an abbreivated or abridged course.
Hope this helps