There is a "double-up" game in my local joints. I'm sure the house edge is probably worse than that of regular blackjack, but I am curious as to how much.

Here are the rules:

1. 6D, H17, DAS, DOA, RSA, 5/6 decks dealt, 3/2 blackjack
2. If the dealer gets 16, whether initially or hitting to it, the whole table pushes unless the player has any type of 21. This includes soft 16.
3. You can "double-up" on your first two cards. Meaning that you can double your bet WITHOUT receiving another card, even after splits. Therefore, 20s and 19s are obviously valuable for this.
4. If you push with the dealer, you lose your double-up bet if you made one (unless the push is a 16 in which case the previous rule applies. You just push). Your regular bet just pushes like normal blackjack.

So how bad is this game? The 16 rule must be killer.