I only watched the first video, but I can tell you that this was not a psychological force. The only remarkable thing was how impressed that girl was with a complete hack. (no offense).

How to devalue a great art into 'card tricks'

watch the second video. remember he says the suggestion is much more subtle.
Before he leaves the table he does two things:

1) with his hand he eliminates 2 of the cards, i.e. he leaves the first three cards out of focus
2) he says "Ok, fair?" and leaves the table

Once the first three cards were eliminated, she could choose between the square and the star. She chooses the square because although he didn't verbally say it, he implied it: Fair & Square

this is no trick, it's simply using people's mind to play tricks on them, do everything he did and may be you will get the same result

where is the 'revealed' bit?

I cannot see the video

is there a tutorial about it !

i can not see the video