230.71 permits a set of up to six breakers or switches to be used as the 'service disconnecting means'. The split buss panels would have 6 breakers feeding things like the electric range, dryer, AC, etc. with one of these breakers feeding the rest of the panel. This 'six throws of the hand' rule is still code.
408.16 would seem to prohibit the split buss panels for new installations.
I guess the 'modern' use of 230.71 in residential applications would be a pair of 200A panels installed for a 400A service, without a 400A main breaker.
-Jon
