Having smoked pot rather intensely for a while, I'm opining from personal experience. Its not just your depth perception while partaking, its you cognitive abilities afterwards, your depth perception, your recovery times,your affected motiviations, your acuity of thought, your short term memory, etc.
All anti -intuitive anecdotes aside, I think we can agree its basically a drug that directly affects and alters the neurons in the brain. Not a trivial indulgence, IMO.
Interesting post when one isn't exactly familiar with how pot affects someone physically. Does seem allot more to this then people want to admit.