The story is not convoluted, it's very simple really. The story is Madeleine was abducted, the window was open to prove it was an abduction and not a walk and wandered and Tanner had to see Gerry and the abductor together, at a time when there was an independent witness present, as it gave Gerry an alibi just in case Martin Smith came forward to identify him.
So as part of the cover up plan they decided to open the window and shutters and say they'd been smashed/jemmied/forced (whatever) - but were both so simpleminded that it didn't occur to them that in order for that to be believed - the shutters would actually have to show some signs of being smashed/jemmied/forced? You really think they were that stupid??
As Gerry could have no idea that Jez Wilkins was going to turn up - then when did he find the time after that chance meeting to hatch a plot with JT (who he hardly knew) - and convince her to lie and say she had seen them and then immediately afterwards had seen the abductor - to give G an alibi? And then after going to all that trouble, why did he ruin the whole 'story' by saying HE hadn't seen JT - thus casting doubt on his own alibi?
I have no idea what use JT would be to Gerry re the Smith sighting, as JT was in her own apartment at 10.00 o'clock - so how could she give Gerry an alibi if M. Smith came forward and identified him?
I can't believe anyone would think that K&G would do all this complicated plotting and planning with windows shutters, arranging alibi stories with JT and all the others having to lie for them, when they could have so easily thought up a much simpler and much safer plan to protect themselves without involving another soul.
And anyway, why would they decide to have a cover-up story which 'commenced' at 10.00 at night, at the end of a long activity filled day when they would all be tired? Like all the rest of this 'theory' - that makes no sense at all.
If you think this is all
''very simple really'' Faith, then I beg to differ - in fact this particular elephant in the room just gets bigger and bigger. imo.