The Esquire tone mods came up because a lot of guitar players around the time Leo was developing the Esquire, were doubling up on bass duties in the days before the bass guitar wasn't invented.
Leo's original intent was to make an electric guitar as simple as possible, his manufacturing capabilities were quite primitive in those early days. If he could get away with a one pickup guitar that could do everything that guitar players were asking for, he would make more money.
He put capacitors in that threw a lot of the high end out and left the bass notes. It's as muddy as hell. Very much a one trick pony. You get some clarity when you wind down the volume and tinker with the tone pot. Can play some mellow jazz on that circuit. The other two settings are normal capacity and total bypass of tone circuit. A bridge Tele pickup that has a total bypass of the tone circuit is pretty raw, especially when turned up loud on modern amps....
I built a Tele as my first Warmoth and originally set it up as a one pickup Esquire. But I found it too restricting and especially with one setting being just about unusable.
I suppose you could do top routing on the JM body and have a pickguard set up for the 2 blade switches and go for it. That way, if it doesn't work out for your playing, you can get another pickguard and start again on some other configuration. :icon_thumright: