I think damage is cumulative ie. you can kill tank with 12.7 mm MG's if you keep firing long enough. 20 mm Hispano is much better in this.
New system will check amount of kinetic energy and thus penetreation capability (which also depends on round/armour angle) round has and compare it against armour. If round can penetrate armour it does damage, if not, nothing happens to tank and round richochets away.
This means that 20 mm Hispano will become much less effective against tanks since it cannot penetrate tank armour unless it is almost perpendicular to top or rear armour. No rounds pentrate armour, no damage to tank.
Also tank vs tank fights will become much more different. No more 4000 yds kills because 75L48 cannot penetrate 80 mm front armour of PzKw IVH at all ranges. Also tank's turret and hull facing becomes an issue, making it neccessary to hit specific parts of tank to kill it effectively.
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jochen / Gefechtsverband Kowalewski
Units: I. and II./KG 51, II. and III./KG 76, NSGr 1, NSGr 2, NSGr 20.
Planes: Do 17Z, Ju 87D, Ju 88A, He 111H, Ar 234A, Me 410A, Me 262A, Fw 190A, Fw 190F, Fw 190G.
Sieg oder bolschevismus!