Rear brakes wear quickly - do I need redundant rear brakes?
The system you suggest has no benefit. The effectiveness of the rear brake is limited by the fact that braking moves your weight forwards and off the rear wheel. The brake you already have should already be capable of skidding your rear wheel. This tells you that the limiting factor isn't the power of the rear brake, but the grip of the rear tyre. Making the rear brake more powerful won't make you stop faster: it just makes you skid sooner. And bear in mind that skidding is not the fastest way to stop&nbsp;&ndash; that (and keeping control) is why cars have anti-lock brakes.

Instead, you need to practise using the brakes properly. If pulling the front brake sends you over the handlebars, you're pulling it too hard. Brakes are not binary: they're not just "on" or "off". Learn how much front brake you can use without endangering yourself (practise on a quiet street at gradually increasing speeds) and remember to brace against the handlebars as you brake so your weight doesn't flop forwards.