This is the correct answer; Brown is right that the front is *more* effective, but both brakes applied with proper modulation are best. However they need modulating separately - the greater grip at the front means that braking there can be stronger.

Brown is also correct that you need to keep your arms "strong" while braking - ie you don't let your weight come forwards. If you can move your weight back that's nice, but not going forward is the real key.

If you can't brake effectively then finding a quiet spot to practice is an excellent investment in your safety.