Anne your absolutely right. No reason to discard the top portion of your root stock that you would normally discard. When you can graft immediately on to it with another scion and re-root it.
Day 2 of the Cucumber graft still looks good. If this takes.. I'd be totally surprised.
If our upcoming summers are going to be hot hot hot.. I'm thinking we need some Getto cheap Air con running on a cheap solar panels to keep our tomatoes cool hehe.
https://www.youtube.com/watch?v=lm0e2TwvXfQ