Often times the rhizome of a variegated banana will start rotting from the bottom and because only a small portion of the upper rhizome is necessary for the plants healthy growth, I always remove most of the rhizome when repotting. We do the same thing when field planting pups, which is referred to as paring.
The lower part of the rhizome causes more problems than it's worth, but it can have value, so before discarding consider potting it separately.
And this is the portion of the lower rhizome of a Variegated Tani I potted a few days ago. Got a double this morning.
