Sounds like interesting organs. Divided stops are, in my opinion, under rated, and tend to appear only in the smallest of organs these days, if at all. Agreed, you have to remember where the break is, so that parts don't stray across it, but it adds a great deal of flexibility to small and medium sized organs. Many early English organs had at least some divided stops, allowing a r.h. solo against accompaniment in the l.h. or vice versa. of course, it's a concept well known to Harmonium players, as the classic French Harmonium always has divided stops - and Cesar Frank's "L'Organiste" includes many pieces which demonstrate their usefulness.