I'm pretty sure that any time I've discussed this, I've said to replace 'em. They don't get better on their own; cleaning just buys you some time. Toss 'em.

A 'treble bleed' cap is a very common addition to the Volume pot. GuitarNuts call it a >High Bypass< capacitor.

You must be the only guy here that I haven't sent to the GuitarNuts website to check out the >Modifications< in their Wiring & Shielding section.