Hi Tim,
Sorry to be asking this so late, but I was wondering about the scale of these doors and their various elements? The reason I'm asking is that the scale may have some bearing on the method of construction.
Larger/heavier glazed (joiner built-ins?) cabinet doors seem to have been made using "sash" type construction per the suggestions you've received, while more delicate barred doors in higher style pieces were often built using a very different method of construction. Thought it might be worth discussing this alternative, but only if it seems potentially appropriate.
Don McConnell
Eureka Springs, AR