In a recent 4-player game I got a triplet of dora tiles and decided to go against dealer's riichi with dangerous discard. It was half-suji though and I actually tried to calculate risk. Generally, dealing into big hand is less likely if you see most dora tiles. It went through. However, on the next turn the dealer called a kan of East winds. What do you think happened next? They dealt into my hand right after their kan. And I got three kan-ura-dora (the same triplet).