Ok, having read through the thread, here's me:
I can literally nail down a shingle in one second.
With a helper throwing them to me (have them trained to toss it at an angle just to my left side), I can grab the shingle, place it and nail it.
Total time per shingle about 2-3 seconds on a pefect application and under ideal conditions (new work, material strategically placed on in field, good weather [like the 40-50 degree range], no drama at home to occupy my mind, etc...).
I'd basically plow through 3 squares at a time and take a quick break (but not long enough to get "cold" or to stiffen up), then I'd hope back to it for as long as I could (which is usually 3 hours straight).
To do the math and to get X amount of squares per hour based on that peformance is not so cut and dry. One has to consider different circumstances, but generally, the best I ever did was 5 2/3 sq's in less than an hour on a 95 degree day "in" the sun.
I once nailed up (but I was especially angry ate my helper who said it couldn't be done) 4 square in less than an hour on a 10:12 roof by myself (no helper).
Today, I'd be comfortable at a liesurely 3 square/hour rate with a solid 18-20 squares a day with a helper on a walkable roof with few if any details.
But those types of jobs here are few.
A heavy detail (dormer, valleys, etc...)...say, 1 sq/hr.
By hand?
My best was 4.5 sq/hour and that's with me loading the roof for me and my dad (that was another day I was working angry! LOL!).
_________________________________________________________
Whenever I do a shingle roof, I will always lay out a bundle or two with my hatchet just because I like it.
But, in the immortal words of Prince's Boss in Purple Raing..."Dit ti biniz!" (This is a business!)
And guns rule.