I've done LSD over 7 times. Each time I would do it just once a month. All 7 of those times I never once had a bad trip. Sure I would see "scary things" but it didn't affect me considering my level of self awareness and my mindset made me realize "hey the weird shit you're seeing isn't real. You're taking LSD remember that". A "bad hit" is typically very rare. Even with research drugs, the high may be different, but the trip all still depends on your state of mind. It's a psychedelic. LSD is known for opening up the deepest parts of you and making you aware of the darkest and brightest parts about you.

If you have the right mindset and are taking the drug with prior knowledge of whats going to happen, I'd say it's extremely easy to control(with average doses). I tripped 5 out of the 7 times at my friends house and his parents never found out. Hell, I even talked to them while tripping and my friend said I was acting perfectly fine. Be careful with your expectations with LSD as that can control your trip.

In my 20's when I waitressed there was this guy who always rode a bike everywhere and would hold conversations all the time with himself. There was no having a real conversation with the guy, it was like he never got over that last LSD trip. one day one of the other regulars told me this guys story. Said he had been a brilliant business man, smart guy, successful but he had a bad hit of LSD and was never the same. Not something I'd be willing to risk myself.
So from the sounds of this, this guy's case, all respect to him, is extremely rare. If you're willing to base whether or not you'd do a certain drug off of one guys bad experience, drugs in general are not for you at all. No hard feelings towards you though. With literally any drug(even the legal ones) there is a possibility that you could experience the bad side of it, it's not just with LSD.