Some players do understand UI. Quick shout out to an opponent from earlier in the week.
Second in hand at love all: S 109xxxx H -- D KQ10xxx C x.
(1H) 3C (X) 4C; (X) P (P) P.'
All calls in the appropriate tempo. 3C (by agreement) was some form of Ghestem showing these suits - no alert. Agreement explained by declarer before opening lead.
When the defenders worked out they both had 4 clubs, they engineered to draw dummy's trumps, but declarer had all side suits covered.
It would be very easy for this hand to bid 4D and very difficult for the playing TD to get an adjustment to +1100 (when +500 in 4DX or 4SX would have been a good score). So "hats off" for passing.