And noise itself is actually "measurement error" at the receiver, which is rarely Gaussian, in fact it really is quite predictable and/or removable.

Noise in the Shannon sense is random and therefore not predictable or correlated. Interference can be both predictable and correlated, and therefore can sometimes be removed / to an extent. Modelling interference as noise means not exploiting its inherent properties, and yes that means ending lower capacity.

"ending up with lower capacity"

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Dr. Ulrich Speidel

School of Computer Science

Room 303S.594 (City Campus)

The University of Auckland
u.speidel@auckland.ac.nz 
http://www.cs.auckland.ac.nz/~ulrich/
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