3 degrees mean a lot, especially at high angles. Don’t forget that it gets to triple overmatch 40mm or less of armour, and double overmatch 60mm or less. Let me show you the difference:
Against 60mm of armour it gets (2 x 1.4 x 122)/60 = rounded up 6 degrees of extra normalisation, which is barely more than an AP shell has. With AP, it would get (5 x 1.4 x 122)/60 = rounded down 14 degrees of normalisation.
That’s one side of the statistic, anyways. The other side is effective armour thickness, even before normalisation. The tank cannot penetrate 60mm of armour angled at 70 degrees with its standard APCR rounds. Normalisation only applies at angles that are lower than that. However, the effective armour thickness of 60mm of armour are rounded down 175mm, which most tier seven tanks can penetrate (if RNG says yes).
If we take 40mm where we can go all the way to 90 degrees it doesn’t look much different. If you shoot 40mm at exactly 90 degrees, which is virtually impossible, you get an impact angle of 81.5 degrees with APCR which translates into rounded up 271mm of armour. The WZ-113 has 255mm of standard pen. However, if you shoot it at 89 degrees you get rounded down 242mm of effective armour after normalisation. So actually, it doesn’t change a thing.
Well, with those overmatchable thicknesses out of the way, let’s see where it actually matters and how much.
80mm - everything up to the ricochet angle is penetrable
100mm - everything up to 68 degrees is penetrable with APCR
120mm- everything up to 63 degrees in penetrable with APCR, 66 with AP
140mm - up to 58 with APCR, 61 with AP
160mm - 53 with APCR, 56 with AP
And so on, I think you get the gist. Now I won’t dig out the standard armour values, but the usual ones are 40, 50m 60, 80, 100, 120 for deck, back and side armour so you can think for yourself how much of a difference it actually makes... and in how many situations. Basically CS vs Gun Rammer all over again