Ok, I've found the problem.

If the grid column controlsource does not have a tablename prefix it acts funny (maybe it's a feature) and expands the memo data out.

For example:

.controlsource = 'mymemo' &&causes funny expansion of memo field data
.controlsource = 'mytable.mymemo' &&results in the expected behavior of 'Memo' appearing in grid column


Thanks everyone.