That is complete baloney. The amount inhaled is just as much under one's control as how much alcohol you imbibe. If you overdo pot you don't lose self-control you take a nap. If you overdo alcohol you get drunk and you do lose self-control.
“If you overdo alcohol you get drunk and you do lose self-control. “
No, alcohol is a depressant. If you drink too much you will take a nap. The problem is the lowered barriers that are in place until you go nappy.
Second, the "amount inhaled" is NOT under someone's control - except for the first hit. My point is that there are no potency labels like there are on a bottle of alcohol, so many inexperienced dabblers won't know what they're getting and experienced "heads" can get blind-sided by laced pot. A toke from one batch may give you a headache and cough. A single toke from another batch might make the room dance for several hours. There is a HUGE difference in THC levels from one batch to another of street weed ("medicinal" pot can be standardized) and it's not labeled - so you absolutely do NOT know how much THCs (or other added ingredients) you are ingesting. If you argue otherwise, I know you don't have a clue what you're talking about.
Say for instance you have a teenager who drove over to a friend's house (maybe your teenager). The kid is offered a bong hit of "something special" before taking off for home (just one for the road to reduce boredom). Having dabbled before with another friend's stash, and being a know-it-all teenager lacking common sense (fairly typical), the kid takes a hit - and lands on the moon. The kid, lacking discretion and maturity in the first place (having decided to ingest an illegal drug), needing to get home right away, is probably not going to display the common sense to "take a nap" and they're certainly not going to call home for a ride. Chances are they'll wait for a bit, then will attempt to drive home. I can think of another 100 scenarios like this - especially as the drug become readily available in homes, on the street, in schools, at work, etc.
And lastly, don't underestimate the amount of carcinogens inhaled from smoking pot. Last time I checked, one joint = 1 pack of cigarettes.
To summarize - alcohol can kill you in more ways then pot. It is much more likely to make you do stupid / harmful things to yourself and others. It can be very addictive, it can give you a hangover, it reduces productivity, and prolonged use will shrink your testes.
Smoking pot can increase your estrogen levels (facilitating man boobs), give you cancer and other lung diseases, you give off second-hand smoke, it causes lethargy, can cause mild paranoia or erratic behavior, may cause hallucinations, and reduces physical dexterity (e.g. reduced reaction time while driving).
Either one in moderation, used at home, are not likely to cause problems. Conversely, either one can cause great harm to yourself or others.