I do not understand what this fascination is with people focusing on the general shape of cores, past and present.
WIll those who are doing so please takes more than 10 seconds worth of glance to realize that while the general shape may resemble that of another ball, only in rare circumstances, when the cover is relatively different, do manufacturers use the same core?
In many circumstances manufacturers, Columbia and all others, can and do change the densities of the 3 or 4 different parts that make up the core to change both the RG and the RG differential AND possibly the mass bias on asymmetrical cores.
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"Just because you can do something does not mean you should do it."