You say that a mountain bike can't be used for touring. I know that it can because I've done it. The touring part of the bicycle's usage would be a small fraction of the daily use and, yet, you reach the conclusion that the touring part is the most important part. A mountain bike would be optimal for the daily use while still being serviceable for the occasional traveling use, albeit not as efficiently as you would like. The touring bike would be optimal for the occasional use while being far less than optimal for his intended daily use. So exactly how is the LHT a more reasonable compromise?