My father is active, but has very limited use of his left hand. Because of this, he has problems pulling the front brake lever and feels uncomfortable doing so at speeds of more than 5-8mph. He is able to shift because chainring shifting is more premeditated than braking is. He has a Trek 4300 that he uses to ride on greenway paths (paved foot/bike paths through parks around town) and more mild fire roads just one day a week. Are there any options for a brake lever that will pull both cables at once? I realize it wouldn't be hard to modify one to do so, but you would only be able to adjust cable tension of one cable this way. Any input would be great on this.