Hi Glenn!
Likely, someone decided that figuring a new pill would serve both supercharged and naturally aspirated people using their weather device.
If you're blown, I think changing the pulley is absolutely the best way to be consistent...making up for nature's shortcomings in available oxygen instead of simply compensating the amount of fuel to get the AFR right. Since you have a "belt-driven manifold", you might as well use it!
So, I'd keep doing what you're doing. It's been working!
Spud