So, currently, I have LML installed with three mods added: Online Content Unlocker, Red Dead Offline, and Playable Van Der Linde Gang. Even after uninstalling these three mods along with Rampage, Lenny's Simple Trainer, Outfit Changer, and Open All Interiors, I'm experiencing this recurring stuttering issue as I explore the map. The frequent lag almost amounts to all-out freezes because the instances each last up to just under a second, making the game borderline unplayable.
BTW, I can confirm that removing vfs.asi does fix the issue, but it's required to use Lenny's Mod Loader at all. I own a legal, uncracked copy of the game that's connected to RGSC, launched through Steam, and updated to the latest patch. I've heard of the game crashing thanks to this file, but not stuttering and certainly not to this radical extent.