We are talking about applying a 25 amp load and then waiting an hour or two for the battery to fall to 10.5 vts at 80F. That is basically completely discharging the battery. Assuming I had a 25 amp load source, that is not something you can do to a starting battery with any regularity as it will shorten its life considerably. I don't know of anyone (even experienced shop technicians) that check or confirm reserve capacity of a battery. Have you ever performed this test? And you cannot trust the rating stamped on the battery. Just look at the Consumer Reports ratings on reserve capacity and you will see many batteries don't meet their specification, just as they don't for CCA. At least with CCA we have a simple and quick test to verify, that is non invasive to the battery.
I believe we all have various priorities and considerations in a battery purchase. Warranty is a big consideration now that Costco has made theirs so weak. Especially with WalMart and Sam's offering four year free replacement on AGMs. I look at warranty, chemistry/construction (prefer AGM), Consumer Reports ratings, store convenience, etc.
I'm not in agreement with you that people exclusively look at CCA in a purchasing decision. Especially BITOG users. People do consider it, as it is one way to easily compare one battery from another, and can be quickly (and inexpensively) tested and verified when new, and throughout its life.
Reserve capacity is typically in line with CCA to a small degree…. Those track together… Higher CCA equals more RC…
More important in my opinion is weight for the BCI size…
A group 24 F battery can weigh as little as 37 pounds…. Or has much as 58 pounds… Exact same size battery case.,
Which one do you think is the better made battery ?
Now that is a bigger indicator of quality than either CCA or RC.