The stern planers are a lot in principle like jug rigs are in thermoclining (Seth green rigs). The same thing can be done with balloon rigs as well and they have been used for years by some of us long before these things were developed. Basically they are just something to keep your long lines way back and above the other stuff such as side planers and riggers etc. These stern planers are just more hydrodynamic.....another tool in the arsenal