Control Freak subframe connectors?

I must work fast when plating - once I pull something out of the plating tank the zinc will begin to oxidize very quickly - you'll see a yellowish-tan color start to appear, so I have to dip it in bright dip and then passivate it quickly.
Once the passivate is gone with time and atmosphere years down the road, the zinc once again oxidizes.
Yes, it is indeed rather self-healing in that the zinc, as long as ANY is there, will protect the steel.
But you can't rely on that long term because the zinc will eventually disappear. 
I can show some welds done using the weld-through high-zinc primer that did show some signs of surface rust. 
I can also take some pictures of the horrible appearance of zinc I left on my tool box - how white and spotted and almost hairy it looks after about a year. Pure zinc, certified 99.99% pure. 

At any rate, I would never personally rely on the zinc primer for protection without doing more as well because I would never be sure that primer got to every single nano-bit of that weld. It would definitely depend on the weld, the heat, the metal being welded and so on. 
I fixed a couple of pin holes after doing the patch welding in a floor recently and you can bet no zinc got to that. 

But hey, I agree, I have pictures to show that I used the primer suggested! So I do believe in it and believe that it does help so I also advocate using it. I just won't stop with that......  ;-)
Call me anal, paranoid, whatever, I want to know that in 20 years it's still good.

I wouldn't rely on weld thru primer as the only rust preventative coating either., unfortunately I didn't state that either in my last post. That post was a copy from an explanation of what weld thru primer is.

But it should protect the weld for a long enough time to prep it for a better primer or a sealer.

The only "primer" I know of that has any life to it at all is a two part epoxy based primer.

I've used "cold" galvanizing coatings (basically paint) which appears to work pretty good.

Even then there's no guarantee that it will remain unscathed, but the chances are better

Got your back Bill,

I haven't experienced everything in my 64 years of life, but I know when a guy knows what he's talking about and that Sir is you.