Mr. Mendelson: KJ was not saying be "accumulated EV" for the future. he was saying that during this day he played with a positive expectation even though he lost
If you really want to know how a blackjack AP operates you could look into computer simulations of the game
they will show you, for example, that despite playing with an advantage there will sometimes be significant losses
with computer simulations AP operations can be calculated with exactitude
for example: if an AP has a 1.5% advantage and plays without error it can be shown that after 10,000 hands he will be ahead 95% of the time (I'm estimating) (95% of the 10,000 hand trials)
....................after 100,000 hands he will be ahead 99% of the time (I'm estimating) (99% of the 100,000 hand trials)
of course, when that 1% or 5% actually happens it can hurt
playing blackjack as an AP doesn't mean you never lose. it means you have a long term advantage
if you want to say that blackjack APs are kidding themselves if they say that large short term losses don't hurt them or effect them you might be right
but I hope you are not saying that playing blackjack as an AP is an exercise in futility
there are literally thousands of people who have profited from playing blackjack with expertise