Healthy reminder: You gotta understand the rule before you break it.
Some of us here use more than two a day, listen every day instead of every other day, taking little to no washout at the end of the cycle.
But there’s one thing in common, we already understood how we react to the base recommendation and adjust after that to fit our goals best. These are for advanced users who understand how they react best to subs. I’d highly recommend you build a solid understanding first using the normal schedule, then reiterate after.
Some opt for more exposure, but some also use less than the recommendation.
That’s something you’ll naturally understand better the more you use subs.
If you think that you get your best results from 15m, then go for 15m, rofl.
Keep a journal of how it goes. Iterate from there.
The only way to know your sweet spot is by experimenting.