Well guys I guess I'm from the old school,I try all the new paint technique's, some I use some I don't, I try to stay with the ones that will work for me .
I have never applied filler of any kind over anything but bare metal, in 50 years I have never had any crack or come off. I have done repairs where there was old repairs and any place there was filler over anything but bare metal it came off easer.
The only time I use etching primer is when I have sand blasted a pitted area.
I use a urethane primer over the filler and to seal the bare metal. Normally I use fast fill easy sand acrylic lacquer primer to do my leveling and filling.sometimes i well use a urethane primer, but it is slower.
When I have every thing like I want it , I seal it with a tinted urethane sealer.
I have some cars of my own that stay outside, and some that stay inside, some have been painted for over 10 years and they will still win paint awards.
To finish, I think that a lot of the new painting systems are designed by engineers and salesman to satisfy the bean counters, And most of them have never been in a body shop or painted a car. I'm sure that some of the younger painters will come on here and say that my methods are outdated, but hey why fix something that isn't broken?
If you don't make mistakes. your not doing anything.
69 ss rs full custom camaro 98 ISCA grandchampion
69 ss rs bb camaro wifes driver
66 Elcamino 350/all dz parts,ac,windows,loaded,my driver
69 ss chevelle bb conv.fresh frame off
26 T sedan street rod