As you know - there are 2 camps
1. spend ages scratching scraping ducking and diving eeking the last bit of performance out of the site today, and ignore the knock on effect for tommorow, because tommorow we can re-gig the effort
2. spend less time and money all the marginal stuff, and concentrate on the SEO core values, which incidentally havent changed that much in the last 10 years. Instead spend the time and money investing in conversion, writing excelent content, writing more content
Whist proponents of both camps will claim thier methodology is the best, the real answer about what to do will depend on the the site in question. One thing is for certian - if you choose to go down the "leading edge" or "balck hat" or "dark grey" route, you are in a constant spiral of work and expense. Essentially, whilst you are trying to get arround a percieved back door, or bend a rule or subvert the result using a new method, Google engineers are equally working hard to close the loopholes, tighten the algorythms etc.. This means, without further attention, the said site dives down in the ratings, and the cycle begins
the "win any way you can" route is fine to an extent, but some bussinesses prefer and need a more long term measured view. Example - Whats the point of clever SEO getting you on position 1 today, to then be demoted 20 pages tommorow, for a period of 3 months, for spamming (or what other marginal technique was employed). I personally would rather be steadily on page 2 for 3 months
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My initial response, as indicated by previous posters was aimed at the typical new website owner, who typically has a site with more fizz than substance, who expects to be on google for little effort. In my experience, sites with real content, unique content, a product people want to buy and want to search for do well. Sites that are poor quality, and invest in spamming rather then content, are like yo-yo's up today, down tommorow