strategy to rebuild/reorganize table with LOBs

I have a letters table, it's 5.6M rows, 405 avg row len, 2837038 8k blocks.
 2 LOBs.  the lobs are in-line.  For whatever reason, these LOBS are mostly
NULL.  Out of 5.6M rows, one of the lobs has 205,398 values, 7900 of which
are larger than 4000 characters.  The other lob has 4.5M values, only 2 of
which are larger than 4000.  This table takes FOREVER to full-scan, be it an
analyze or an export, select count, or anything else that requires a full
scan.  Additionally, queries against indexed columns result in long run
times with a lot of LIO/PIO.

I'm having some row chaining/migration problems with this table and it
appears to be a good candidate for a rebuild, with a new values for PCTFREE
/PCTUSED.  The table currently has a PCT_FREE of 40 and PCT_USED is not set.


I dont know if the fact that the lobs are inline(or the lobs in general) are
causing issues, or if the values for pctfree/pctused is.  I can say that
this is the worst performing table in my application.  Im thinking of
export/truncate/import this weekend but want to make sure its done
correctly.  I thought a value of 40 would be ok for pctfree.  The lobs and
how they're being used, with all of the NULLS are throwing me for a loop.
 I'd appreciate some help in configuring this table for export/import.

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