WOw...you just kept repeating yourself!!!
And yes, there IS a train between T5A and T5B!!!
As someone who has to work in the thing, I do not think its all that its trumped up to be but its definately the best thing going in the UK because lets face it, you brits are not good at developing infrastructure. Some may not like its contemporary feel but I rather like it, personal preference I suppose. There are clocks ALL OVER the place....they are on the flight info screens. The UK Boarder thing is a new concept which is being introduced by immigration all over the UK. As to point 4, you clearly were acting the maggot, they did the best they could with two people who clearly did not want to play along. Perhaps the trial day that you were taking part in did not require the need for "DIFFICULT" passenger trials. They may only have been running tests on systems and jettys etc.
T5 will definately be a vast improvement on the rest of LHR. You may not like the look of it but you just need to go over to the central area or T4 and realise that you aint gonna do much better!