Don't disagree with any of that - just making the point that although the Goldstone in its prime had a capacity of 35K (or even a tiny bit more), we didn't get 'many' 30K plus crowds back then - they were the exception, not the rule.
Many times? I'm not too sure about that...........
I have been there in a 35K crowd (1972), but 30K crowds were the exception rather than the rule - and in subsequent years the ground capacity was progressively reduced for safety reasons. I can't quote all the figures, but by the 87-88 season...