A previous boss did this in the early 2000s. Put up a bunch of single page descriptions with "coming soon" labels, include an email subscription to "stay on top of news", turn on AdWords to get some traffic... and then start working on what people were actually interested in.
Yeah this seems like the kind of thing people would have advised me to do when I was trying to start startups around 2010. But I was too focused on engineering and had no head for the business side so I never tried it.
Ya, I know this strategy under the name “smokescreen mvp”. I don’t remember exactly, but I think it is advocated in the lean startup. Personally I am a big supporter of the strategy. Many startups fail because _nobody cared about the problem_, and this is totally avoidable