> What on Earth are you storing in JSON that this sort of performance issue becomes an issue?

I've been in the industry for a while. I've probably left more than one client site muttering "I've seen some things ...".

If it can be done, it will be done. And often in a way that shouldn't have even been considered at all.

Many times, "it works" is all that is needed. Not exactly the pinnacle of software design. But hey, it does indeed "work"!