We now have a dedicated SEO strategist who, among other things, develops 90 day plans for our websites. 90 days isn't longterm planning, but at least we have a strategic objective for the quarter. He also works closely with our UX team to identify the target audience - the crew that does the persona research and focus groups prior to the wireframe stage.
Not all strategies have to be big. Sometimes your window is small, and you're forced to build for a distinct — or tiny — opportunity. Maybe you don't have time for a proper large-scale strategy at all; a tactic or two might be all you can do to carry in a win. Just make that very clear with your boss or client. Don't misrepresent what you're trying to build as an SEO campaign.
Black hat SEO attempts to improve rankings in ways that are disapproved of by the search engines, or involve deception. One black hat technique uses hidden text, either as text colored similar to the background, in an invisible div, or positioned off screen. Another method gives a different page depending on whether the page is being requested by a human visitor or a search engine, a technique known as cloaking. Another category sometimes used is grey hat SEO. This is in between black hat and white hat approaches, where the methods employed avoid the site being penalized but do not act in producing the best content for users. Grey hat SEO is entirely focused on improving search engine rankings.