*Why "D4"?  I normally get asked,  and gets jumbled with A5 (which happens to be a climbing quality), and D5 (which stood for "Deuce5"), two makes I have already been involved with in past times.  My nickname in Yosemite was "Deucey", coined by Grant Hiskes  who mangled my Friesland ancestral identify "Middendorf" to "Dusseldorf",  and Deuce4