The point of the data is to give a generalized conclusion of whether or not polishing the internals will help a marker's efficiency, regardless of configuration. Using each person's individual gun and only changing the variable of the polish job should give an indicator of whether or not the gun is behaving differently and its significance. There is still a debate on whether or not polishing the internals even does anything for a marker. By giving hard evidence, people can see what affect it has on a gun's performance.

Now I don't believe all the data collected can be used for all guns. For example, lets say that the polish job gives an increase in 30 fps or a drop in 100 psi (random guesses) for all the data given. Like you said, with so many different variables, such as paint used, chrono used, gun mods, receiver half tolerances, etc, in addition to different guns (a5, x7, t8, etc) that there is no way that the numbers can be used to apply towards everybody. That's why I would like everyone to do their own personal test so that they can only compare the before and after effect with themselves.

However, a general rule of thumb can given and proven based on the results rather than just going by people's word of mouth. The results can be binomial in that they either do or do not give a signficant change/improvement to the marker.

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