At which point and using what method was the McCann's word thoroughly tested by SY? You are just guessing.
The only reference I recall is a forensic examination of the timeline. What forensic examination? Using which method? A pen and paper? A high tech software program? Certainly not a real live actual reconstruction. After all that would have been far too risky for the McCann's chums.
Do you have any idea or will your answer just be another supposition?
If you really believe that SY did not thoroughly investigate the parents as their No. 1 priority, but just took their word for it that they did not dispose of their dead child's body then you are being very disingenuous IMO.
The family are always the first people to be investigated so that they can be ruled in or ruled out at the very beginning. I thought everyone knew that.
If you can at tell me how a one off reconstruction could be carried out and how the PJ would deal with the problem that only approximate timelines were able to be given by 10 different people - I would be very glad to hear it.