Well we quickly hit a snag when testing our creation script the second time around, when it wouldn't let us drop the materialized view log:
SQL> DROP MATERIALIZED VIEW LOG ON FOO.BAR
ERROR at line 1:
ORA-00600: internal error code, arguments: [kkzlpllg:5], , , , , ,, , , , , 
We found that we also could no longer perform fast refreshes of the materialized view, getting the same ORA-00600 error. Our initial MOS search turned up Doc ID 14158012.8, which indicates Bug 14158012 (Orphan rows in SNAP_LOGDEP$ causes ORA-600 [kkzlpllg:5]). The bug description is:
With this bug, when there are orphan rows in SNAP_LOGDEP$ with RSCN=NULL,
a CREATE MATERIALIZED VIEW or DROP MATERIALIZED VIEW statement will report ORA-600 [kkzlpllg:5].