I hope it is not too late for you.
Even if you have the physical data structure on the disk, it is far from taking conclusions whether the situation is good or bad.
I am not an SQL expert. My main area is External Fragmentation. I am exploring into Internal Fragmentation, and lookong for a counterpart in the SQL side.
If someone is challanged, please have a look at
my site, where I describe the concept, and answer me through the site.
Thanks,
Koby BILLER
DISKLACE