The effects can be predicted by looking at which receptors the individual drugs work at.
You can make generalisations, but
you can't predict ahead of time how you will respond to a drug you have never taken before. You don't account for allergic reactions, idiosyncratic responses, or the whole set and setting thing. These are all factors that cannot be downplayed. You also can't make predictions about how much two drugs will potentiate each other in a given individual.
It's usually the effect that is dangerous, not the presence of the molecule.
This is meaningless weasel wording. The effects are there because the molecule is present, and if the molecule is present it produces effects. Just because the mind feels sober doesn't mean the body isn't effected. You do not re-establish equilibrium immediately after the drug "wears off", there are indeed residual effects. Your liver doesn't care how high you feel - the enzymes still respond to drugs, and some drugs induce changes that stay until well after they have cleared. (like MAOIs).
Many drugs, or their metabolites, alter the metabolic rate of other compounds. Some potentiate each other exponentially. Some secondary metabolites are still active.
This entire evening is probably far more predictable than any of you want to imagine. I respect that you believe otherwise, but really, I believe you're exaggerating.
Who are you trying to convince with this sort of talk? The best laid plans of mice and men oft go awry, as it were. What if you get hit by a bus? What if plans change? What if the MDPV makes you go all binge-crazy?
Especially benzos and opiates. Why are people freaking out about benzos and opiates when they're not even going to be active at the same time?
Because benzos and opiates results in respiratory depression 9 and a half times out of 10, and because the combination is more lethal than either alone.
MDPV and alcohol have been mixed many times. MDPV and GHB have also been mixed. There shouldn't be a problem with this as long as both are taken in moderation.
MDPV is not a drug that leads to being "taken in moderation". And yeah, PV and all sorts of shit has been mixed; that does not mean it's a good idea. Especially given that PV leads to erratic, paranoid behaviour in a lot of people. Which, again, you cannot predict ahead of time.
The worst thing that can happen is embarrassment, I think.
This kind of thinking will be the end of you. The worst that can happen, of course, is death.
All in all, not that crazy a night.
13 drugs in a night isn't "that crazy"? Do you fuck polar bears at bedtime and play badminton on the Interstate freeways before you've had your morning coffee?
If you knew better than us about the safety of your binge, why did you ask? It sounds to me like you are trying to convince
yourself, not us. There are just too many powerful psychotropics you are trying for the first time to say that it is "predictable". Many of them alter your mental and physical equilibrium for quite some time - drugs do not clear out of your system like flipping a switch.