I agree on all counts, with exception to the "drug-free for a lifetime" comment. I wonder if this former DEA agent has drank a cup of coffee or used tobacco.
It could be that the DEA has specific disqualifications when it comes to past drug use...that would be interesting to look up. I could be wrong, but I think the past drug use guidelines are stricter in some agencies than others, such as the FBI vs. the CIA or Defense.