Surely a lot of the MRA4's problems arose because, while most of it was designed by BAE, some bits of it had been designed by DH 50 years previously?
Well, when you try to fit a computer designed wing built to a gnats c*cks tolerance on a hand made and built fuselage, your wing will naturally fit the one you used to take the measurements, the rest however, not a hope in hell.
You then install an engine that was never envisaged nor designed to work down a long intake ducting and you are exasperating your problems.
Nimrod had served the RAF well for many a year, to blame it on items designed 50 years ago is not a problem with the DH design, but a problem with BAe not understanding the foibles of the design and contruction and then not addressing them in the contract, nor in the build.
http://www.spyflight.co.uk/mr4a.htm