[Imp]

Okay me bad switched fast arty off yes it seems to if hits anywhere other than front assumed it was just a stray shell landed by it.
Think you suggested & in line with urbans post that it delivers 2 warheads (air more) you could reduce the warhead size to try & stop it hitting more than 2 targets. It does however deploy them at 1000ms on delaying fins so it has time to search for targets & probably should hit 2 most times if in the area.
Tend to keep 50-100m between tanks most of the time if expect it so had not really noticed just took as bad luck if 2 died.

As a note the mortar variety should only hit one (Bofors site & mortar)
The powerful version with sensors should probably generaly hit the top as arty models that it can hit sides more often in fact I think Koh said the penetration is probably boosted to reflect that