The Rams have a young quarterback in place. They have a higher choice in the 2012 draft. They do not have a general manager, meaning Fisher could play a leading role in hiring one.
Those are the factors Schefter cites, while noting that Miami might offer more money.
Reports from Miami have indeed said the Dolphins will not be outbid. However, the absence of such reports out of St. Louis should not be construed as evidence suggesting the Rams feel differently. We should make no assumptions about what Rams owner Stan Kroenke might or might not pay, in other words.