I polish the internals of any pistol I have. I don't see the point in waiting for it to wear in by firing when I can do it in a few minutes. There's no way anyone can spin polishing as a negative thing. Don't want to do it? Fine, but there's no way it can hurt anything and gets rid of a factory gritty trigger.
Glockyourdoor pictures are a good example. Unless someone convinces me that glock designed the pistols to have corrosion on the parts then it shouldn't be there. They are assembled from parts pre made for long periods of time. If glock hand polished the parts the price would go up quite a bit.
I'm personally not going to spend a ton of money waiting for the trigger to get better, I prefer to have it from the start. Polishing gets you the best trigger you can get without modifying/changing parts. I have been working on guns for decades and have never seen a gun get messed up from (hand, not dremel) polishing trigger parts. In fact a lot of people pay to have it done. I have seen a lot of dremel mess ups.
Polishing takes nothing except light corrosion off the parts (again as noted in the pictures), no way it can be bad. I don't know about fishing reels but the parts should not be corroded. Will it wear in? Of course, but it makes sense to me to remove something not designed to be there.
Bob Beers is right. A lot of factory guns have jagged edges and burs in them also, they are assembled not fitted. Maybe because I work on guns but I see no point to not going through the trigger assemblies. Stone the jagged areas and burrs, polish the points.
I'm not telling anyone they need to polish their internals, just that polishing removes corrosion that was not designed to be there.
If someone can prove that glock designed the parts to have corrosion then I will retract my statement.