Standing on the Shoulders of a Wiseass

The phrase "standing on the shoulder's of giants" has a long and interesting history, generally taken to mean building on past successes of others.

One of the most famous uses of this quote is by Sir Isaac Newton  to Robert Hooke:

What Des-Cartes did was a good step. You have added much several ways, & especially in taking the colours of thin plates into philosophical consideration. If I have seen further it is by standing on the shoulders of Giants.

While reading  Is God a Mathematician by Mario Livio, I came across an explanation for this quote I hadn't heard before.  Newton, know for his rivalries and disputes, may be been taking a swipe Hooke's stature and severe stoop.  The Wikipedia article on the quote seems to refute this by indicating that Hooke and Newton were on good terms, at least when this letter was written.