Sounds like words of common sense to me. And if you are from Delft, I suppose it saves you the drive to and from Brussels or Dusseldorf then?
It was more a case like planning to spend two weeks in the US office and planning on flying straight back home (AMS), when some business pops up and I had to do a few days of work in Boston before flying out.
Europe fares from Amsterdam are fair, enough low-cost and charter companies to keep the main carriers on their toes. Decent US deals can be obtained too, though I have to admit that LHR is generally cheaper. But for me the convenience of direct transatlantic flights is worth some money. (Not to mention the hassle of dealing with luggage that didn't make the LHR connection.)
I never bought tickets with the intent to skip a segment.