Firstly, the passages in question do not say anything about public places. Secondly, pot does impair thought processes, reaction time and so forth. In other words, it does not leave you sober and clear minded as we are admonished to be.
And I posted a clear example out of many that it does not. Believe what you will in spite of the reams of objective research that, in addition to my ancedote, proves otherwise. Just don't advocate using the indescriminate and brutal power of the state to enforce your beliefs.