good penetration
There are 2 factors that are important when it comes to getting lots of penetration in a 6d or dd game:
1) You should find a casino that's not up-to-date when it comes to surveilence. Harrah's, Monte Carlo, Flamingo and Tropicana are all good choices.
2) You need to get on the dealer's good side. They're the only that can help you when it comes penetration. If they don't want to cut the deck deep you got no shot. Tip early and often and the dealer will certainly consider helping you out.