Sorry if I came across as overly critical - I wasn't suggesting that your conclusion is invalid, but that the experiment would only apply to a fairly narrow class of website (e.g. "mortgage-leads... business-leads... diet-pills... and ringtones"), and that you may not have varied the design significantly (screenshots would have been great!). The 'cheaply-designed' thing was uncalled for, and for which I apologise; I think I was trying to suggest that a different 1024 design style may make a big difference, but it came out snarky, probably because I'm working on something frustrating.
It's been working (big time) for us ever since we switched all landing pages to a "thin" design.
And no, we don't promote a cheaply-designed diet-pill website. SEO-driven, yes. Money-making, yes.