It was a long process to arrive at this scenario.
Dissecting all the statements showed that their friends were all lying about certain points.
The first breakthrough was the realisation that it was Dianne who was the only truthful witness. She contradicted some of the most important statements, like the checking routine, Matt's listening check, that Gerry and Matt were probably missing at the beginning of the meal and the statement that the McCanns did not go to the Millenium for breakfast.
If she was the only one telling the truth then the most important question: "When did you see Madeleine for the last time" was only truthfully answered by her. The Wednesday evening at the Tapas children's dinner was the last time she was seen by a truthful witness.
On the other hand we had the lies about her whereabouts on Thursday. The insistence of most of the Tapasniks in the beginning that Maddie had been at the tennis on Thursday and the absurd scene where all were watching the children's tennis none of their children took part in, while Ella was sailing down at the beach, for me was the most important indication that Madeleine had not been there on Thursday.
Apart of course from all the other indications like the other stories with the only intention to show that she was alive on Thursday.
The next huge puzzle-piece was the statement of the cleaner.
The fact that Maddie's bed had been used Tuesday night but looked almost unused on the pictures of Thursday night indicated that it had not been used on Wednesday evening/night.
The fact that the cot had been moved as well on the Wednesday or Thursday supported the fact that at some stage a body had been stored in the parent's bedroom.
All this narrowed down the time of death to 17:30 - bedtime on Wednesday.
When I read Jane's rogatory statement about the tantrum thrown by Ella only recently for the first time, it all slid into place.
Never mentioned before why would she part with this in her rogatory interview? Combined with their frantic search for more info from the files it seemed that they suspected more from Mrs. Fenn than the Tuesday crying.
The change of routine on Thursday developed more and more into a show to keep Dianne away from the truth and even the staged evening and detection of the abduction pointed in that direction. It was just an additional bonus to detect the changes in Russel's statements where he first states that he collected Ella at the tapas area to change it to a much earlier pickup from the creche. At a time when he was still swimming....
As to the reason why the Tapasniks complied I am still pondering the theory that they - and possibly even Gerry - where deceived as to the real reason of her death.
Maybe they still think she died while being alone in the apartment, maybe even Jane helped Kate with the hysterical child and supplied a sedative, but it does not change my conviction that she died falling off the sofa while trying to look through the window for her father. A fact they tried to hide by lowering the shutters of that window AND closing the curtains.