Flybar:
AMS is of course a European hub - and one of the best from a pax transfer point of view.
However, WW are just a loco carrier that offers point to point travel only. So, if for example you want to fly from EMA to, say Moscow, you would have to buy your ticket from WW, and pay all the money-grabbing supplements for seat reservation, baggage, credit card payment and whatever else they can think of to charge for; then buy another ticket from KLM for the AMS/MOW leg. On arrival in AMS you would have to pick up your bag, go through arrivals (immigration controls), then recheck-in, or at least do a baggage drop in departures before going back through border controls, and to the gate for the AMS Moscow leg. A right palava.
If you book KLM from BHX, LBA, MAN or wherever you check in at the UK departure airport, along with your bags, get two boarding cards, and apart from security processes at Amsterdam it's seamless transit to Moscow. You don't touch your bag until it arrives, God willing, on the carousel at the Moscow terminal.
Moreover, if you compare the costs of a through ticket on one carrier (say KLM) from a UK airport via Amsterdam to pretty well anywhere, with adding the costs of two separate tickets (UK-AMS then AMS-destination) the latter option will almost always be more expensive.
This is why EMA simply fails East Midlands business by not being able to offer a proper ailrine service, with interline connections via anywhere other than Brussels through British Midland and the Star Alliance hub there - and Brussels is by no means the best interlining hub in Europe.
egnxema is quite correct in that instead of having pipe-dreams about long haul the management needs to start sorting out "proper" airline services to serve the business community, most of whom currently travel either via BHX or MAN.