Most definitely NOT the case.

I first encountered the dog screening on Wednesday late afternoon at IAH. Normally I go through Terminal C checkpoint, where precheck line is often longer (but still moves fast). But saw my flight was leaving from E and decided that might save me a 20m walk. Huge mistake! The lines at Terminal E were massively backed up beyond the ropes - it was as if there was no pre-check as everyone had to funnel through some area with the dogs. After waiting a minute with no progress I took the escalator down and walked to Terminal D. There were no dogs there but the lines were ultra-slow due as they were filled mostly with families going international and there was a modified pre-check (e.g. all electronics out but no MMW). I still think I came out ahead but who knows - at least the walk wasn't too long.

My initial assumption was that the dogs were there to sniff out narco-traffickers but perhaps that is only part of the mission. Would like to complain but don't want to be flagged SSSS so I guess I will just suck it up and avoid Terminal E. Hopefully we don't see this nonsense at SFO. Found the whole thing outrageous and pointless.