Based on my experiences, redosing on the same day/trip is fairly useless. I can trip harder if I want, but it takes a significantly larger amount of said drug (I'm only experienced with mescaline though, not any RC phens-yet). The next day my tolerance is generally lower although still there. After about a week or so I seem to be back, or at least very close to, baseline. It kind of sucks because I can't stagger my doses with psychedelics like I can with dissos, so I always have to get the initial dose right. If I want to intensify my experience, I find that weed helps a lot, but not everyone likes weed with psychedelics. Like with everything else though, I'm sure it differs from person to person. My bf can redose psychedelics on the same day and trip just as hard, but I also use them more frequently so I probably always have some level of tolerance. My tolerance has never quite dropped to where it was when I first started using psychedelics but it's still pretty low as long as I wait a day or two between trips.