Posted 03 February 2013 - 10:26 AM
I feel that there are many factors in head shape. If you look at the Long Nose woods of the feather era you will a lot have some concave look to the face and as they got to the gutty era they became a little flatter. Not much face progression as the feather ball launches high. The gutty being harder and much more lively the heads had more loft. As the socket head woods came into play most were pretty flat as Bella said and this was with the gutty. Some heads exhibit large face progression around 1900-1910. As the wound "bouncy" ball came into play you see less face progression and start of the bulge and roll. Some of the Spalding models in the early 30's are great shapes and were designed by J Victor East.
I have always felt that face progression had a lot to do with ball launch. This is true with woods and irons. This design feature of course has a lot to do with the ball played at the time.