Husker 1911, not sure if you mean filing out grooves on the followers or filing out the dimples themselves .
Filing out grooves on the followers... that would work on some of the solid polymer followers and maybe on that Vang Comp. On the old-style steel followers that I have, however, the metal is pretty thin. If you file away enough for the dimple, you've filed through the metal!
Filing out the dimples... well, they do serve some function as far as keeping the magazine cap more securely in place. Sure you can just crank down on it with some pliers, but I'd rather leave the gun as designed (as crappy as the design is) and just buy a quality follower that fits.
I'm going to start with the 1100 I use for dove and the 870 I use for duck. Those see more shots through them than the others. Much more likely to empty the magazine while hunting.
I have two other 870s I use for turkey, but turkey hunting is more often than not a one-shot affair. And my HD 870 already has one of the old-style steel followers. Dimples are gone on it since I had to remove them to add the mag extension.
May get one SS and one colored aluminum for a comparison.