For comparison purposes I have taken photos of three different era
Tech heads to make a point. First, a pre-war Canadian. Notice the thickness:
Next is an early 70's
Tech head (on the pre-war handle):
Finally, a Chinese branded
Tech:
These changes do indeed affect the shave angle and perhaps more. The latter is up to the user. The last one is pure pot metal and although I love the shave and maneuverability the light weigh is a disadvantage. This makes the middle one, which has a brass base and a pot metal head, as the better shaver IMO as it is more nimble and able to reach tighter areas with more ease. As well, the blade rigidity is a frog hair better. YMMV.