I'm happy to report that I made it on the flight from Guadalajara to Houston.
Once on the ground in Houston I walked four miles (I'm estimating, it could have been 22) to get to the Global Entry kiosks. I was the only one there and did my entry and got my receipt in a couple of minutes. Then I waited in line (yes, I was the only one there) until the BP agent decided to call me over and take my receipt.
Then I walked seven more miles (again, an estimate. It could have been 102) past luggage claim (I only had a carry on), past customs and into an area where we were corralled to wait to go upstairs to go through TSA. That took about 10 minutes.
Once upstairs I saw the mob of people and asked an employee for the TSA pre-check line. "That's downstairs." The same downstairs I just came from? Yes.
Back downstairs I went. I asked the lone employee allowing (or not) people to get on the escalator to TSA. Traffic control, I assume because it was SRO in the TSA lines. She told me to go outside, upstairs and look for the Pre-Check signs. I did. And they had them...randomly.
The actual answer is that Houston does not have TSA Pre-Check for passengers connecting from an international flight. I was going outside and coming in as if I'd just arrived at the airport.
Once I finally found the Pre-Check line (after walking about another 24.6 miles) there was a problem. It seems not all the TSA employees realized it was Pre-Check so they were letting anyone who strolled up get in line. Finally, an enterprising young woman took charge and separated those of us who actually had Pre-Check from those who were in the wrong line.
While waiting in a line a guy behind started louding saying "This is why we need a wall. Am I right? We need to stop these people coming in here. Build that wall, build that wall." I'm not sure why he assumed a wall would help, unless he was thinking that Trump was just building one around the airport to keep anyone without TSA Pre-Check out. It was hard but I did not respond. No eye contact, no comment. I believe I hurt myself by keeping it in. The best part was as the woman started separating us the guy got really made because a bunch of people got to go ahead of him. Because he didn't have Pre-Check and was in the wrong line.
After another 10 minutes, I was through and laughing about "wall guy".
I checked the gate monitors and saw that my flight, which didn't leave for another 3 .5 hours, was at gate E1. Just a quick 39 miles away.
Thanks, United - I got my steps for today.
BTW, there's a sign next to one of the escalators in the Houston maze from international gates to TSA that says "Senior Citizens - do NOT use escalators. This is for your own safety." I used 'em anyway. What are they going to do, take away my Global Entry status?