I take this lightly now because I no longer care about publishing, but it’s actually quite sad. I won’t be re-writing the paper to make the reviewers like it; instead I’ll post it here in its current form for anyone to do with it as he or she pleases.
Download the paper.
Download the MATLAB code to generate the Nyquist-modulated signals (poorly commented and uses functions from the free Optilux library and the communications toolbox).
The proper citation would be
M. Winter, “Nyquist Pulse Signalling for Spectrally Efficient Terabit/s Superchannels,” utterly rejected by Photonics Technology Letters in March 2011.
The print version would have had an addition acknowledgment section, mentioning fruitful discussions with René Schmogrow and Wolfgang Freude from KIT, which I forgot to put into the draft but which really is quite important. As far as I know, René will keep pursuing the idea. I wish him more luck with the reviewers.
last posts in Nyquist WDM:

One of the reviewers actually requested a reference to a relevant paper by the Poggiolini group (there were already two references to papers by that group on that topic in the submission) – oooh, I wonder who that reviewer could have been…
Damn, that sucks! Die Idee hatten wir auch und wollten das demnächst mal ausprobieren ;-) Mal schauen ob das klappt.