While that theory is sound (when focused on a single page, when the intent is to deliver utility content to a Google user) using old school SEO techniques on especially a large site spread out across many pages seems to amplify site quality problems, after recent algorithm changes, and so this type of optimisation without keeping an eye on overall site quality is self-defeating in the long run.
Basically, SEO keyword research should be an ongoing and ever-evolving part of your job as a marketer. Old keywords need to be reevaluated periodically, and high-volume, competitive keywords (or “head” keywords, as opposed to long-tailed keywords) can often be usefully replaced or augmented with longer, more specific phrases designed not to bring in just any visitor but exactly the right visitors. (Who visits your site – particularly if they’re people who are actively looking for your services – is at least as important as how many people visit.)
The reality in 2019 is that if Google classifies your duplicate content as THIN content, or MANIPULATIVE BOILER-PLATE or NEAR DUPLICATE ‘SPUN’ content, then you probably DO have a severe problem that violates Google’s website performance recommendations and this ‘violation’ will need ‘cleaned’ up – if – of course – you intend to rank high in Google.
Google expects pages to “be edited, reviewed, and updated on a regular basis” especially if they are for important issues like medical information, and states not all pages are held to such standards, but one can expect that Google wants information updated in a reasonable timescale. How reasonable this is, is dependant on the TOPIC and the PURPOSE of the web page RELATIVE to competing pages on the web.
QUOTE: “I think that’s always an option. Yeah. That’s something that–I’ve seen sites do that across the board,not specifically for blogs, but for content in general, where they would regularly go through all of their content and see, well, this content doesn’t get any clicks, or everyone who goes there kind of runs off screaming.” John Mueller, Google
If you are improving user experience by focusing primarily on the quality of the MC of your pages and avoiding – even removing – old-school SEO techniques – those certainly are positive steps to getting more traffic from Google in 2019 – and the type of content performance Google rewards is in the end largely at least about a satisfying user experience.
Because someone who is looking for something that specific is probably a much more qualified searcher for your product or service (presuming you're in the blogging space) than someone looking for something really generic. And because long-tail keywords tend to be more specific, it's usually easier to tell what people who search for those keywords are really looking for. Someone searching for the head term "blogging," on the other hand, could be searching it for a whole host of reasons unrelated to your business.
QUOTE: “The average duration metric for the particular group of resources can be a statistical measure computed from a data set of measurements of a length of time that elapses between a time that a given user clicks on a search result included in a search results web page that identifies a resource in the particular group of resources and a time that the given user navigates back to the search results web page. …Thus, the user experience can be improved because search results higher in the presentation order will better match the user’s informational needs.” High Quality Search Results based on Repeat Clicks and Visit Duration
Place strategic search phrases on pages. Integrate selected keywords into your website source code and existing content on designated pages. Make sure to apply a suggested guideline of one to three keywords/phrases per content page and add more pages to complete the list. Ensure that related words are used as a natural inclusion of your keywords. It helps the search engines quickly determine what the page is about. A natural approach to this works best. In the past, 100 to 300 words on a page was recommended. Many tests show that pages with 800 to 2,000 words can outperform shorter ones. In the end, the users, the marketplace, content and links will determine the popularity and ranking numbers.