Alright, I just tried a test similar to what was posted in
this thread on an actual miniature.
I took a German Marder I from Battlefront that I had primed using watered down black acrylic paint (i.e.
not a "true" primer). This is what I have been using to prime for several years.
This model has a resin hull, and metal tracks, gun, gun shield, and crew.
Just like the experiment in the linked thread, I used regular masking tape. I placed a strip of masking tape on the resin hull, and pressed it down on the miniature for maximum adherence. Then I slowly pulled the strip of tape off. On the resin hull, there was absolutely zero paint loss.
I then did the same thing on the tracks and the gun shield. On the tracks, there was some minor chipping in two places, the biggest part being above the back two road wheels.
The gun shield had the most damage, but it was primarily on the raised areas, and still relatively minor in my opinion, and certainly not as massive as the damage done in the experiment involving the flat piece of metal.
I get a very smooth finish using this technique, and this hasn't really made me want to switch to an auto primer. I think that with varnish (which I always use) and problems with chipping can be avoided (not counting drops and other major damage, of course).
So what do you guys think? Do these results match your experience or expectations?