The phrase "watching the flow of cards" is associated with the voodoo belief that you have to keep the same number of hands in order to make the dealer bust and has nothing to do with card counting. Card counting remains the basic tool to detect an advantage situation. Alternative techniques do exist but they require very special conditions and very special skills. Actually, I do use shuffle tracking whenever it's possible but this has to be seen as an enhancement to card counting.
By the way, I had to build up a bankroll and I have to live from that money.I'm not betting as heavily as you imagine (3*200 max)but even like that the swings are wild enough. Yet, I can assure you that it's totally reliable.
Francis Salmon