ash666
Obviously when its busy the security will be worse. But that happens everywhere and even LHR can sometimes be very slow.
Just for my interest when going by train to LHR from Newcastle station, on arrival at Kings Cross I presume you either have to drag your baggage onto the underground and connect via the Piccadilly line to LHR which has a journey time of about an hour.
Or get the underground to Paddington, then get the Heathrow Express to Heathrow.
Does the Bus go direct from LHR to Newcastle ?.
Re the KL to AMS. Its obvious from your previous posts that you have a problem with the NCL service. I agree that there have been baggage problems but the situation should be improving. As for the flight punctuality, well delays are actually few and far between and under normal circumstances(ie no ash cloud) cancellations are also very rare indeed probably less than many other carriers at NCL. They must occur mainly when you travel, perhaps your unlucky.
Most problems seem to occur when the onward is not with KL in which case it can be difficult to deal with certain issues.
Connections via AMS are usually very good. But thats just my personal opinion.