I recall reading an article some time after the Erebus accident where Boeing and other manufactures changed their GPWS pull-up procedures from a recommended 15 degree pull up to a 20 degree pull up manoeuvre.
The article stated that Sundstrand (it was their GPWS system?) did some research on CFIT accidents and came out with figures that indicated the "average" CFIT hit the hill at 300 ft from the top at 230 knots and the "average hill" which is hit had a 18 degree slope. My figures may be a bit inaccurate but it was close to that.
15 degrees was the usual body angle for go-around in most early jets and by default was the body angle which pilots aimed at during a GPWS pull-up. By going aggressively (meaning real fast) to a minimum of 20 degrees - as well as firewalling the throttles, you played the law of averages and hoped you won on that occasion.
A vital simulator exercise to be practiced until competent, in my opinion.