Quote: "You comment about domestic UK flights to LHR being low, Edinburgh is the top UK connection point and it has over 10 flights to LHR per day. Bristol is close to LHR yet its second in line for connections. Turning to Europe Amsterdam has endless connections all over the world, yet its the top connection airport for EI to the US."
Wasn't commenting on the frequency of flights from the seven airports linked to LHR, just the fact that there are only seven!
Compare that to DUB and AMS which are each linked to over twenty.
Travellers from most UK airports do not have the opportunity to connect via LHR, even if they want to.
Quote: "Pre clearance does not impact a lot as many don't know about it from Europe and the US side."
You sure about that? It's a good USP for EI, you imply that they're not marketing it properly.
Also bear in mind that only a few USA destinations are available from DUB.