Well I gave it a try. I decided to go with a marketing strategy of doing nothing.
It as been 5 months, during which time I have sat back and watched what happened (with a bit of writing and real life going on in the background). I didn’t tout my books in any way at all: no ‘buy my book’ tweets, no KDP free promos, nothing. I didn’t even update the blog.
How did it go I hear you ask? Did your sales nosedive? Do you regret such a silly experiment? The answer to these questions is ‘no’. Whilst I did notice a steady but slow decline in sales via Amazon, this appears to have been matched by an equally slow but steady increase in sales via other outlets (only possible because I had withdrawn the books from the KDP select programme). This was achieved despite a social media silence with regard to marketing, which leads me to the conclusion that it is less effective than some would have us believe.
However, I have a confession to make. During this time I did try some less overt marketing. I succeeded in making one of my titles free via all outlets (in the USA at least – I’m having more trouble getting Amazon UK to price match). Whether it helped or it didn’t, it required little effort on my part so I’m happy to stick with it.