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I know You don't aggree, but once again, in this certain situation I stick to the suggestion of an internet pro, who bets 1/4 to 1/3 of the pot on a scary flop.

You don't want to loose much in the RIO situation and I think this kind of bet is the best You can do. If Your opponent is sitting on a draw, he has the pot odds to call or he might reraise. But I don't see a better try for me. If he isn't on a draw, it's not that easy to deal for him with that kind of a bet. Because he can't be sure whether we are on a draw or whether we hit the straight, reraising in this situation isn't that easy for him.
Betting 1/4 or 1/3 of the pot doesn't commit much money if I get reraised - in which case I fold - but sometimes may lead to a cheap showdown, if he calls.