What I find odd about this ability is that, opposed to other HE shells, it has obscenely high pen and AoE pen (same as the regular AP shells). This means it can quite reliably outright destroy support weapons instead of just decrewing them. It's also surprisingly effective vs armor (if you manage to hit, that is) for that reason, although each shell will only deal 160 damage.
I don't think the barrage needs to have that high pen values as it should primarily be an AI tool. However, playing around with it I noticed the shells don't seem to have a proper animation for deflected rounds (shell just disappears w/o sound or visual FX), so maybe the almost guaranteed pen is a poor-man's fix for that?
Based on https://coh2.serealia.ca/#147 , Wonder why Jadtiger HE barrage had 520 pen ?. That mean if a heavy tank stay in barrage area. It would take full damage from 4 shot ( if all of them hit target) ?.