You-Tube's very variable advice on oiling-out and varnishing

Some of you I know avoid YouTube, as diligently as I avoid WetCanvas - because the advice available on it can't always be trusted. Of YouTube - on the whole, there are good artists there offering good advice.  But I stumbled upon a US painter giving extremely bad advice, unfortunately supported, to a degree at least, by a paintmaking company (also in the US). The two points are "oiling out", and varnishing.  She routinely adds oil to her paintings when completed - a process usually done by applying a very thin coat of added oil, and removing as much of it as possible having done so: the oil then seeps into the paint, and will enhance its colour.  It's a useful practice if you paint has undergone the process called "sinking in": the umbers, especially, can do that - sit there sullenly, duller than when first applied.   However, there is no need to apply oil over the whole painting - if you do that, the colours might be enhanced at first; but they'll run a strong risk of yellowing later.  Oil does yellow to a greater or lesser extent, but there's no point in encouraging it to.  So mistake number one.   Mistake number two, and this time she's aided and abetted by Gamblin oil paints, is premature varnishing.  She says that science has moved on, and there's now no need to wait 6 months before varnishing: she shows the old, wholly mistaken, trick of trying to dent a paint film with her finger nail; if it doesn't give, it's dry and you can varnish it .... Gamblin asserts that its Gamvar varnish makes this a safe practice. Now - I'm not a scientist: but Mr George O'Hanlon, of Rublev paints, is; and he doesn't trust this practice.  Virgil Elliott, an internationally respected writer on oil painting and a highly regarded professional painter, doesn't trust it either.  The advice of both of them is to wait 6 to 8 months, depending on the thickness of the paint.  They recommend a particular type of varnish, which you can find more about by reading Mr Elliott's Traditional Oil Painting, or visiting the Natural Pigments website.   OF COURSE it's annoying, or frustrating, having to wait a while to varnish; of course most of us love short-cuts.  Painting, however, is for the patient - once the creative urge has spent itself, and you have your finished painting, those oil paintings need to be treated with the respect due to them: that means not lathering them in extra oil if it's not needed, and allowing them to dry naturally.   Robert Gamblin may be right about his Gamvar - the long term will tell us.  Perhaps he has devised a formula which has the very few virtues of Retouching varnish, modifying whatever might lie in his permanent picture varnish.  On the other hand, perhaps pictures - especially those on stretched canvas - will crack and craze like wild things farther down the line.  With many of mine, that wouldn't, frankly, matter much!  But you - whoever you be - shouldn't take the risk. 

You certainly have to be very discriminating - neither you nor I are likely to fall for bad advice, but what concerns me is this: people WILL go to YouTube, and the inexperienced by definition won't know if advice is sound or rotten.  I think you avoid Facebook too - I look at a couple of sites, including Virgil Elliott's: he implores people not to offer their opinions unless they've fully researched them and know what they're talking about; but still people post nonsense.  Virgil removes it, and it must take him hours per week he'd be far better spending on painting or writing.   He's quite a stern administrator, so has his work cut out: all discussion to be based on his (excellent) book and questions relevant to it - nothing about water miscible oils, which he likes and trusts about as much as I do, but still people post innumerable questions about, of all things, brush cleaning - questions which have been answered before, answers available on the page's files - but it's so easy to sit at your laptop and type away without bothering to consult the recorded information.  (Which is basically what I'm doing now, of course!) He's managed to exile the Bob Ross fans, and he has an open argument with Mr Gamblin...  if inexperienced artists could restrict themselves - to his site, to Alan O's, certainly, to the Painting Best Practice pages, to artists with an established record and obvious competence, rather than to breathless Americans who took up painting just months ago and are actually selling their work, now believing themselves to be experts, rather than credulous dupes - well, the world would be a better place!  Snag is, they don't - and I hate to see people being given bad advice. Whether my earnest correctives achieve anything, on the other hand, is a moot point...