I haven't read about it in quite a while but I think maybe it's that the psilocin is already destroyed by dehydrating the mushrooms, but cubensis (i've assumed that's what you have) are mostly psilocybin in the first place so it's not a big deal, whereas other species like Panaeolus cyanescens have much more psilocin and potency drops big time when they're dried. I sauteed some fresh cubes once and they were really wonderfully flavorful and i tripped as hard as expected for the dose.