What I'm trying to say is that the physics of the shockwave won't make a fundamental difference, whether it's produced by HESH or HE.
The impedance of air is very small. In contrast, explosives have a higher impedance. The shock wave from the explosive to the armor will have more energy allocated to the armor. The shock wave from the air to the armor allocates much less energy to the armor. This is why HESH shells should stick to the surface of the armor as much as possible before exploding.
What I disagree with is that induced overpressure has a high lethal rate. Note: The induced overpressure is generated by the transmitted shock wave.