Good article. I would only mention that in order to fix ordering issues you don't necessarily need to change the clustered index. ALL indexes are sorted, so a correct index may remove the sort and changing the query may remove the sort operation as well. For instance if you have an index on LastName, FirstName but then you sort on FirstName, LastName, the index may still be used but you'd have to have the sort operation in the query, where an index on FirstName, LastName would likely serve the results up in ordered fashion so the sort operation would be unnecessary.