Last night I was looking at my cheap Chinese (never to buy again) shoes and realized that after 150 miles or so, the soles were separating in places and some of the threads were looking pretty frayed.
So, I took out my hot glue gun and reglued the soles and put glue over the places the threads were getting frayed and reglued the soles.
It appears the repairs have worked. I wouldn't trust them for multi-day hike, but they are certainly good enough for local training hikes to save putting miles on my new shoes.
Maybe I can stretch the life enough to wear holes in the soles and put cardboard inside to cover the holes.