Cleaning records. How often really?

Oh, wait a minute Bill. The Last Preservative is not designed or intended to remove the mold release agent (allegedly, if you prefer) found on new LP's. Nitty Gritty at one time offered a product named First for that purpose, but it's no longer available. The Preservative is to be applied to an LP after it has been completely cleaned. I don't know how widespread your opinion of the product is, but as always, better to error on the side of caution, especially when an application is permanent.

Does anyone have evidence that mold release compound MRC is used in the manufacture of LPs or CDs?

Bill, it is my understanding that all records are pressed with a thin coating of a mold release agent applied to the stamper. If the stamper is not so treated, the LP's resist detaching from it after the cooling phase of pressing.

This seems to be true, but according to what I've read on Vinyl Engine, not every pressing plant uses it, and if it's used, it's a judgement call by the operator on when to use it.

Release agents are used for tool and die parts in manufacturing, wherever parts are being molded.

Effischer, ideologically I share your view even though I called it 'insane approach'. But I think this would be too much work and very inconvenient arrangements for me. I will machine clean the records I play after 10-20 plays or every year. And of course I will use Last record preservative. Every serious audiophile I heard of does it. There are also records that I don't play, they are for archive, I will clean them every 10 years, maybe. I keep copies of a few albums for future generations or if there is an accident and I lose my playing copy.

Reasons to wet clean a record more than once include:
1. the initial cleaning was inadequate; or
2. the record was re-contaminated during playback or storage.
Compulsiveness aside, there are no others.

To avoid #1, clean each record thoroughly the first time (to whatever standard of cleanliness you prefer).

To avoid #2, play and store cleaned records to avoid re-contamination. This would include steps to:
a) remove dust;
b) reduce vinyl's propensity to attract dust (ie, static); and
c) shield the record from dust when not in use.

I have my methods, developed over many years and after many trials and comparisons. My standards are high but my tolerance for re-cleaning is low. Therefore, every record sees an extensive cleaning, playback and storage regimen.

It works, at least for me. I'd estimate that 90-95% of the records I clean do not benefit from a second cleaning. OTOH, a similar percentage of records "cleaned" by friends do benefit from a second cleaning using my regimen. YMMV, of course.