Well, no - Harris draws on the English Roundhand tradition, and seems to have made an effort to present an alphabet which is optimal for writing with a pen rather than engraving. Hence the unsquared tops and bottoms, for instance. It's more like a late 17th / early 18th century hand, and none the worse for that in my opinion.
In this book, "The Art of Calligraphy " 1995, David Harris show this script as "Copperplate" which is, as you described it, with unsquared tops and bottoms.
In his later book "The Calligrapher's Bible" 2003, he shows this same script as "Copperplate, Italian Hand". He then shows a second script as "Copperplate, English Roundhand" which is more traditional with squared-off tops and bottoms (which, BTW I greatly prefer.) However, there is a serious problem with the ductus he applies to this latter script as it would be impossible to write as indicated.
Many upstrokes are shown as shaded which (as anyone who has attempted to write with a flexible nib will tell you), is impossible. Beginners will be totally frustrated if they try to follow these directions.
This is a great pity as otherwise "The Calligrapher's Bible" has many good things in it with good exemplars.
Ken