Hi Redewenur,
Forgive me but I was'nt refering to the Cosmic Microwave Background, but to the Universes Constant Expansion.
I didnt explain myself very well when I said the Red Shifts won't change, but there might be 'fingers of protruding matter', or even depressions.....we just could'nt prove their existence,
since we
assume that equal Red shifts of equal brightness means equal distances from us. which is further strengthened by the assumption that Dark Matter, thats causing our expansion is in (constant?} production, everywhere?
However put another way.....similar Galaxy distances don't always produce similar Red Shifts.
'Tired' light that is coming out from an 'above average' higher gravitational Galaxy than normal, or light that has travelled further than we suspect due to its gravitational bending on its way to us, are just two cases in point. Or even light that has travelled thru a dusty environment.
The fact is there is no guarantee that similar Red Shifts of similar brightness, are all equidistant Galaxies.
Without a distance guarantee, there is no speed guarantee, making for further complications.
Or to put it yet another way....it could mean that there is no proof that Dark Matter is produced uniformly throughout our 'spherical' Universe.
Therefore since true 'far galaxy' distances cannot be proven, then the known universe cannot be proven to be a true spherical shape.
Which , as I stated previously, is what I believe.
Its an interesting discussion, but I dont believe either of us will come to any conclusion, due to the unproven variables concerned.
http://www.iop.org/EJ/abstract/0264-9381/15/8/016 
