NTFS metadata/$Secure:$SDS fragmentation

[Chris]

I just wanted to see if anyone out there knows whether security
descriptor fragmentation is a problem. PerfectDisk reports
fragmentation in the $Secure:$SDS datastream as an issue. It seems to
me that this datastream is not likely to be accessed contiguously, so
it should be benign. Is that true?

I would assume that fragmentation of the indexes ($Secure:$SDH and
$Secure:$SDI) is much more of an issue.

Does anyone have the inside scoop on whether fragmentation of the main
data store matters?

Thanks for your help.