OK. I spoke to a really friendly and knowledgeable fellow up at The John Eagle Sport City Toyota of Dallas. I'd post his name to his credit but I don't know how his employer would feel about it. Anyway, he also agreed that the line to caliper tube could very well be the culprit. And he also told me how and why. The fluid that was working thru the damaged caliper could have easily got so hot that it melted the inner layer of the tube. So with that and inafogg's opinion and everything else I've read, that's what I will go with for now. I will post the results.