The Lin posting tool isn't working for me so it's here:
https://www.bridgeba...SA|pc|SJ|pc|S5|
Ok, so having a look at how a couple of players managed MASSIVE percentages in the Daylongs (do they have several accounts so they have already seen all the boards?). In any case I came across that one where a player made 3NT+4 for a huge score and had a look at the play.
It looks clear to me that West who is getting squeezed in 3 suits on the run of clubs will have to yield a trick in hearts but at the end you need to play the final card from dummy (ace of hearts) and so North has to go down to a single diamond which means he'll have to overtake the queen with the ace and partner can hold the suit.
Ok, that may be tricky for an average human in the East position who doesn't realise the value of the 7 of diamonds but we're talking about a robot here who is not expected to miscount things, and should be able to work out that the spades in hand are useless and covered by partner but he'll be squeezed if you don't guard the diamonds.