I suppose if I do a split, can I go back and combine before the main flow to get more honey, or would this be counter productive? May be another question for another day.
Going into my second year here myself, but IMO, if you split, you will have another hive........ with a queen. If she's a good queen (good brood pattern, calm/nonaggressive) why would you want to combine? Next year that new hive might very well be your best producer. Besides, by combining it seems to me you would be recreating your "overcrowding" situation all over.
Again, just a "new bee" opinion.