CELKO (11/22/2012)
Most often non-RDBMS people use their generated physical locator as the cluster because this is how a magnetic tape or disk access modle of data would have done it.
That may be true for non-RDBMS people but others realize the value of it in preventing page splits of the data involved in the CI. Page splits are horribly expensive things both CPU and I/O wise on heavily inserted OLTP tables. Page splits are a frequent cause of massive GUI timeouts.
If a table is mostly static, then I agree... the clustered index should be used for something else. If the table suffers a lot of inserts, then a CI on a narrow, ever increasing, and unique column such as an IDENTITY column or a DATETIME column and an IDENTITY column as a uniquefier is generally the way to go. And, yes... it's very much like mag tape requirements. It worked for mag tape and it works here.
--Jeff Moden
Change is inevitable... Change for the better is not.