The only time I'd use a linking only strategy is if there actually WAS content but Google could not see it (A Flash only site comes to mind).
Otherwise, it's just a numbers game and the deck is stacked against you.
Why? Because anytime you buy a link, so can I. It comes down to whoever has the deepest pockets and the biggest link farm (which eventually goes back to deep pockets again). Mexican standoff, and Google controls the bullets.
But at the end of the day, basing your whole strategy on links is short term thinking - it's the new keyword stuffing. It doesn't add value to the site, and although it's working today it doesn't mean it will work tomorrow. All those people stuffing keywords into every nook and cranny back in '97 would have told you flat out that there was no way ever that a search engine could beat their keyword stuffing algos and systems. Then along came link analysis
The problem is that links seem to be the new bandwagon. Although not new, there is a very new emphasis on links to the exclusion of content. Whenever I hear someone talking about links being "king" (whatever that actually means) the underlying tone is that content is dead.
And that's just plain wrong.
I saw this a lot in university - particularly with the young crowd who came straight out of high school and thought they were REALLY smart because they got accepted into University. And then (horrors!) they learned stuff in university that they did not know in high school, and felt that this secret knowledge was really the key to it all. Right after that they typically became rabid pro- or anti- whatever the focus of the day was (programming models, political theories, social theories, etc).
The insidious part of the problem was that they are often NOT wrong, but rather so focused on one thing that they fail to realize that the world is a complicated place, and there is NEVER a single cause for anything substantial or complicated - no matter how attractive the theory is or how influential and well spoken the main proponents are.
The issue isn't right or wrong, the issue is actually understanding interactions.
Let me illustrate in an SEO environment.
The first "Content is King" proponents were spammers. Normal people put up sites, talked about their subject, and linked to and from related sites without much regard for search engines. Spammers figured out that the SE rankings were related to content and, ignoring links, focussed on keyword stuffing. metatag stuffing, cloaking, and so forth. No doubt they thought they were very clever for figuring this out, to the detriment of the web in general.
No doubt many justified their actions by saying they were "just doing what their client wanted" (it's your actions, not your clients - be an adult and admit it - it has nothing to do with client knowledge or permission) or that "everyone was doing it" or that it was necessary to remain competitive or any of the dozens of other reasons they chose (anything sounding familiar here?)
Then along came link analysis and all these people who had put all their eggs in one basket turned into crybabies. The smarter spammers learned all about links and started generating link farms.
The rest of us went on our merry way, since nothing really changed except some spammers lost their jobs for a while and the SERPs got better.
Now, recently, the "links are king" crowd are going:
"whaaa! sandbox! - my bulk link buying isn't working"
! the toolbar hasn't been updated - how am I gonna buy links now? What if that PR 7 is really a PR 2?"
"Hey! those 30,000 footer links I have, and all my forum post sigs, don't count anymore!"
"I'm doing great on Google but Yahoo and MSN (or the reverse) don't like me! Why not?"
How come the only people saying these things are those who are on the links are king and content is dead bandwagon? and how come they haven't taken the hint? Personally, I'd consider having my site drop like a rock and staying dropped as a hint that maybe whatever I was doing before, I should probably stop.
The first thing you do when you find yourself in a hole is PUT DOWN THE SHOVEL! Don't start digging harder. Don't start asking people if you need a new shovel. Don't start a thread on proper shoveling technique. Put down the shovel, take a step back, and look at the big picture.
Here is a hint:
Make the best website you can (content)
Let as many people as possible know about it (links)
And you will be successful. I know, it sounds crazy. Everyone should try it sometime, just for laughs. You'd be surprised.