That's exactly what I'm doing, Bob. A smaller spare, though. 700/25c lightweight folding tire. That way it'll take up as little room and weigh as little as possible, but will be enough to get me to a bike shop if I need it. I'll buy a more suitable replacement tire at the shop and put the spare back in my pannier. I'll still be taking less weight than a big heavy touring tire, but will have a faster rolling tire with a better ride, and supposedly rotating weight is the most important.

While figuring out what Bob is saying sometimes reminds me of the scene in "Ocean's 12" where they meet Matsui in the cafe to talk about the job , I interpret Bob to be saying "If you tour on really light tires, you would serve yourself well by binging a spare 'cause there is a good chance you will need it."

It works for Me .. even with sturdy tires .. I brought a spare .. left the one with a Burst Sidewall in a farmer's Tractor shed, in Scotland.

I've done several tours on slicks. When buying new tires, I request them. But the last two times, the bike store had none in stock. So I ended up with tires with a bit of tread.

I don't notice any difference in the feel of the ride with or without treads. I travel on paved roads 99.99% of the time. When I ride on gravel, I slow down. I avoid riding on sand.

I get about the same number of punctures with treaded and untreaded tires... I think width is more of an influence. (32 mm: rarely. 28 mm: once in a blue moon. 23 and 25 mm: once or twice a season.)

+1 on the Hypers
I have toured on them and commute daily on them (700x35). No real issue with flats, and they ride fast and comfortable. They have been fine off road and on wet road surfaces, and I avoid slick mud, so no issues there. Just about to buy a new set. On the other side, they don't seem like I'm going to get 4000 miles out of them, my guess is somewhere around 3000. But I think the quality of the ride is worth the loss of mileage.

I believe in Conti Gator Skins above all else. I don't know if they come in the 26" size to fit 95% of the LHT frames, but they are the best if you're only going to tackle pavement. You won't need bigger than 28mm either if asphalt is your only playground. Gator Skins can go very long stretches without punctures and I have tested them multiple times to reach over 3,500 miles.

Here's the cheapest on the web for anyone else interested. Rocktown Bicycles | Products

Also, never buy steel beads. Those things are awful compared to folding beads.