Pai Gow Poker - Understanding the Odds

So, I'm interested in picking up Pai Gow Poker for my next trip to Vegas. I've dabbled in it before and read the Wizard of Odds about it but I still have some questions that I could use some help with:

The WOO says that I should split two pairs with 2 exceptions: If the sum of ranks of the pair is 9 or less when holding a K or A and a sum of ranks of 15 w/ A. I understand how to play the rule but would like to understand why to play it. Why with higher pairs would I only keep the pairs together with an Ace singleton and not a King as well? It seems like I would have a better chance of winning with them split.

Also, I remember getting paid out on having a good hand with my 7 cards. Is this a bonus bet and if so, what are the odds? Should I take the bet?

Thanks!

Splitting two pairs is advantageous with high cards (all face cards generally; Kings and Jacks for example); It is better to keep lower pairs together with an ace, and very low pairs (6's and 5's or less) with a King. Lower pairs if split cannot support a winning hand, and often lose to two higher pairs split, when they would push (tie) if kept together.

A strong-ass basic strategy for Pai Gow Poker is below:

1. Pai Gow hand (all high card singletons): Play Highest card in five card hand, 2nd and 3rd strongest on two card side.

2. One pair in full hand: Always play the pair in five card side, with next two strongest cards up in two-card side.

3. Two pairs:
a. Always split Ace-high two pairs.
b. Always split jacks and 7’s or better, except when having an AK for the top.
c. Always keep two-pairs 6’s and less with any King or Ace for the two-card side, else split.
d. All other two pairs split without an ace, but keep together with an ace for the two-card side.

4. Three pairs: always play the highest pair in the two-card side

5. Three of a kind, simple (NO flush or straight with it): Split Three Aces 2-and-1, (with joker on 5-card side if one ace is the joker.) All other three of a kinds (Kings and less) never break up, and play next two best cards as the two-card side.

6. Two three of a kinds: split off a pair from the higher group for the top.

7. Straights and/or flushes:
a. Straight or flush with one pair: If the pair is Jacks or better, and the top is Ace-face or better, play as one pair if the straight or flush has a queen or less top.

b. Straight or flush with two pairs:
i. Always play as a straight or flush with an AK or AQ top.
ii. Always Play as straight or flush if playing it as two low pairs would have a Q or lower top. (6554332 play as 53/65432, not 64/55332)
iii. Else treat as two-pair hand.

c. Straight with Flush: if either the straight or flush has a Queen or better top, then play the better top; if both tops are Jack or less, then play the stronger flush.

d. Straight or flush with three pairs: Always play as a three pair hand.
e. Straight or flush with three of a kind: always play it as a straight or flush with pair or ace up. (Play 9888765 as 98765/88, and AA*2459=A2*45/A9)
f. Straight or flush with full house: Play as flush or straight if it has a higher pair for the top, else treat as full house, below.

8. Straight flush or Royal Flush: Always handle as straight and/or flush, above.
9. Full house:
a. If you have a full house with an extra pair, then play the higher pair up;
b. If your full house’s pair is 4’s or less, keep with AK or AQ, else split off the pair part of full house as the two-card side.

10. Four of a kind:
a. Always split four Aces 2 & 2, unless there’s a pair of 4’s or better for the top.
b. Keep foru Kings or Queens with an Ace-Jack or better two-card side, else go to next step, c.
c. Split four K’s or Q’s 3 & 1 with an Ace-low (for an AK/AQ top with three of a kind K's or Q's), else split 2&2.
d. Keep four 10’s or Jacks together with any ace or pair for the top, else split 2 & 2.
e. Keep four 7’s through 9’s together with any King or better top, else split 2 & 2.
f. Keep 6’s and lower with a Queen or better top, else split 2 & 2.

11. For four of a kind with a three of a kind, split a pair from the higher group for top.

12. Five aces: Always play a pair of aces up.
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Bonus bets: there is always a "Fortune" or "Dynasty" Bonus bet that pays on a three of a kind or better, and often a Pai Gow Protection or Insurance bet that pays if you have a 7 card hand with no pair or better in it (all high card singletons). I generally play the bonus bets because the house edge is reasonable for a multi-payout table bet, and because they're fun to play. See the Wizard's Pai Gow Poker page

There is also a commission-free Pai Gow Poker version in many casinos that nevers charges a commission, in exchange that the dealer hand pushes if the dealer has exactly a queen-high Pai Gow hand (Bonus bets are always active). See: EZ Pai Gow. Both versions have about a 2.5% house edge (Commission Pai Gow Poker is 2.73% when not banking, and EZ Pai Gow is 2.47%.)