I've worked with a few stadium architects, I don't remember any being millionaires or even much better paid than me tbh...... and very few had any experience in acoustics. None had stood on the Gwladys St against Bayern or saw the original Goodison Rd terrace (with over 20k capacity) in full voice, or on the Kop when we took full advantage of their tin roof either. So I'm not sure what your point is. I've said already that as a rule of thumb the single tier end stand is in most ways the best approach for unifying and spreading chants, but it is not the only factor, and is never the way to maximise capacity for a given footprint, more so with the re-introduction of standing. As a for instance: if GP had always been just single tier with the normal pre-war format of say 2 side stands with small paddocks and 2 end terraces.... our record attendance would only be about 50k, and the capacity would now be about 27k. Could that have been a better atmosphere than the actual 78k record and numerous other 50-70k+ games too? Would any people in that single tier stadium enjoy better views than the current upper tiers? The answer to both questions is obviously no.