You have a contradiction when you talks about page splits on inserts.
Ascending Sequence:...Once a page becomes full, it stays full; resulting in little or no internal fragmentation.
Descending Sequence:...The internal fragmentation is the same as
the ascendingsequence scenario; at or near 100%.
Either Ascending should be "at or near 100%" or Descending should be "little or no fragmentation".
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