How so? You'll most likely use this ability in conjunction with a ram, which will mean the Elefant will be backing up trying to save itself and into the path of the rocket plane targeting the rear armor (and due to collision, it's more likely to get struck then), or when the Elefant is snared and it'll be too slow to (fully) dodge it anyways.
And tripple PTRS was introduced to give Penals more alpha damage against lights. It hardly had anything to do with fighting tanks, let alone heavies/superheavies. They have the AT satchel for that.
Ram was nerfed but that's not the point.
Back in the last year, i though this nerf (pen nerf) was at some point implemented and told my AT partner to use it against the rear armor. At which he told me he was missing on several occasions and the dmg was inferior. After testing (and recognizing that pen nerf was not implemented yet) we found it was better to use it frontally (Tiger/KT/Ele) as it was more reliable dmg.
Regarding PTRS, yes, i know the point was fixing their intended role which was lacking (the light vehicle phase against specific vehicles). I'm pointing out that since 2013, the only/main approach Soviet had against long range TD has always been ram + offmap.
I don't think satchel nor current version of Penals PTRS provides enough pressure or motive for someone to back tech T1 in order to counter Ele/JT.