Bill I never said That I do not use an optokill - I said I use an RcEXL one.
I use Life batts. That have 2 Futaba /JR type plugs. 1 goes to the Rx switch and the other to the CDi switch.
The out wire of th CDi switch has the diode.
The diode wire of the switch then goes into the optokill and then onwards to the CDi.
Hence the battery is isolated from the CDi and so is the Rx.

2.4 Ghz systems are inherently less prone to interference.

I use the 1 battery system for only upto 20cc engines/ models. Beyond 20cc or models with digital servos, should be run with 2 batts. May be even redundant/ 2nd battery for the Rx.