Q - Does it work?
A - Yes. That's why they dont allow it.

Q - Is it legal?
A - Yes.

Q - Can you get away with it.
A - Yes, to a certain extent. If you change your bets dramatically, when the cart are +12 or better, the dealer/floor/pit/cameras will count the deck with you, so they will know.

Q - Is it still possible?
A - Maybe. In the UK, we have automatic shufflers now, so at least 7 decks are being constantly shuffled, so not really. In Vegas, im pretty sure they still hand shuffle a lot, so counting is easy enough.

Q - Is it hard?
A - Yes. I tried to do it once, I good at math, probability, odds, percentages, and studied maths. And i messed up a few times.


Summary - Dont bother, it wont make you rich.