This doesn't really make sense because when you 301 those domains to your regular domain, you'll be passing on all link juice, and those domains won't appear in search results. You won't get a bonus just for redirecting good keyword domains, unless they have backlinks to them. Once the search engines crawl the page, and you redirect it, what's stopping the search engines from crawling the page again and picking up the redirect?
This feels to me like it would be gaming the system. When your instincts tell you that, either it already doesn't work, or if it does, the search engines are working on ignoring it as a signal.
I like Shane's way.