Not try to start anything here but I have to say my personal experience tells me that blasting and painting seals the "rust seeds". I've never heard the term "rust seed" btw. Then again I'm always willing to learn.
I agree completely about using phosphoric acid for rust. It works for sure. Personally I like a large spoon tank (electrolytic rust removal) or blasting and paint ting but phosphoric does work well also.
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First, there is NO ELECTROLYTIC rust removal. It is a misnomer for the process of electroplating rust off one object and onto another, or attracting the rust to a carbon based electrode it will not stick to and filtering the rust out of the electrolyte once you figure the filtration out. Only been doing it for 30 years now and my tank runs 24/7 with clear electrolyte, no scum on top, and does the job. The electrolysis occurring in the solution is less than occurs charging a wet cell battery.
Second, All metal is porous, more so with rusty metal, and no blast media gets all the rust out of the porosity. Metal is normally blasted to the gray iron standard, meaning the inspector can see no brown rust on visual inspection within 1 hour of blast.
Solid media, of the sand nature, regardless of media, be it sand, aluminum oxide, black beauty, glass or any other hard media peens the micropores shut with rust still in them. 20-30kpsi water does a better removal leaving less rust behind and doing less peening. Believe me, water is very hard and hits dam hard at 20kpsi.
Microscopic bits of rust peened into craters and pores sit there waiting for water and the game is back on. Old saying rust never stops is absolutely true. Once the rust seed finds water it will grow and exert force. That combination will spall any coating over the rust, and the blister will grow.
The only way to prevent recurring rust is to soak the iron in Phosphoric acid solution to thorough wetting. That will convert the rust to Iron Phosphate.
Phosphated iron offers two benefits, the first being rust killing. The second benefit is Iron Phosphate is a coating enamel will adhere to, so the primer layer and priming process can be eliminated from the job.
Phosphating works so well I often let objects from my electroplating tank flash rust so I can then phosphate and coat. I have many objects that now have a 30 year life on the paint.
I've also run molasses chelation on rusty objects when time was available to do it.