It can help when shooting throu that enemy who is covering a capper or decapper though I would rather nade trick in that scenario rather then use a heart piercer. Also if you all alone facing a Zerg of enemy comin at you but they have to line up to get shot again but thou I would use nade tricks or throw a long/mid and short nade in a confined space and just play a fighting retreat to slow down an enemy whilst I retreat to a better fighting position I think confined spaces would help you optimize heart piercer say like a narrow corridor/walk way or entrance / exit FYI I have barely ever used it I.e I think the last time i used it was when it first came out. Some people swear by it but they typically have a much higher skill set than I
Be a man and bring it with khorne for the ultimate situational lols. Also, see that melee teammate engaged with an enemy? You no longer have to walk around him to hit the enemy
Heartpiercer is more of an assist weapon, the initiator and main damage dealers should be another's cqc bolter, you use it to keep dps up during fight coming from an unexpected vector as can catch them lined up and even down some in the heat as they are damaged. Your priority target during this should be their apoths as they will attempt to heal their brethren and for that they have to be adjacent, nicely lining up during the process. Lsm protocol of dealing with downed player on ticket maps: Man down, shield gets infront, apoth comes to pick up the downed. Now if you have Heartpiercer can pick on the apoth behind the shield and finish the downed at the same time, although one would agree an tricked grenade does this faster and better. However apparently nade-bursting is scheduled for removal in a future patch so do not rely too much on it. I do use it with MoK as its one of the three weapons(the other two being autocannon and stormbolter) where the otherwise laughably inefficient lifesteal can be of any minor use due to hitting multiple at once.
I always found myself not shooting as to not kill my teamates whenever I used it.The 2 seconds in a match where it is useful is not worth the bother imo. I guess if you are a one class kinda player it wouldn't hurt to take it as your alt traitor loadout.
