My subjective sense is that there are only a few schools where denial of tenure isn't the end of the line for research professorial dreams.
OP's notion of the 7-year postdoc is an interesting one.
That's sweeping, overstated, and unfair of me, but the job skills are quite different. Applied, directed research aimed at producing tangible and sell-able results is very hard, and by-and-large not what they do, at least based on who applies and interviews (which is of course a terribly biased and perhaps non-representative selection).
The real point though is it's a lot easier than many other fields.
I think it's much easier in Computer Science than other fields - say the humanities, or biology or chemistry.
I more or less endorse the article. Seven years is a lot of time. I'd only give someone new a little bit of advice.
(1) Do a good job of your teaching, but economize on the effort you put into it. (2) Be civil to everyone, from the department head on down to the janitor. (3) Do your service/committee work as asked, and do it cheerfully, but for the most part don't go the extra mile. (And when you do go the extra mile, do so because you believe it's important, not because you believe it will win you brownie points.)
But above all:
(4) Kick ass in your scholarship.
There are plenty of sources that purport to break down and explain (4), some of which are worth reading, especially if caught in a rut -- but if you are successfully kicking ass, and paying at least minimal attention to career advice when it comes your way -- then I'd only worry about continuing to kick ass.
That is my perspective anyway.
Asking somebody at a high-tenure-rate, second-tier school to treat their tenure track position as an extended post-doc is essentially asking them to have a failed career, on the other hand.
(it's worth noting that Harvard has actually changed tack recently, such that they're increasingly promoting junior faculty...the above is still true regardless, at least for the time being)