Are you really sure about this?  And is it only for SQL Server?  Every hot fix I have ever installed for another product explicitly states 'this hotfix is deisgned to resolve the particular issue described here, only apply it if you are experiencing these symptoms'.  A hotfix rollup, well that's fair enough, the name itself says 'this is all the hotfixes since the last service pack' but that's exactly what you would expect, it's a rollup.  I have never seen an individual hotfix that includes previous hotfixes.

Craig