Other than the absense of a gate agent, I can't see what makes this different from the e-ticket/home check-in systems used by many US airlines. In the US, security checks the pax ID against the boarding pass -- pax may or may not have to show ID at the gate.
I think echeck-in is used primarily on domestic flights in the US -- I'm not sure if it's used on any international flights -- but in any case, at AMS pax need to show both passport and boarding pass at exit immigration, don't they?