I agree with billvon on this one. I've never liked having one hand on each handle. I think that makes a jumper more prone to potentially pulling the reserve before cutting away, but to each their own on this one. In regards to the OP's question, I think that looking up at your malfunctioning main is an unnecessary step. You already know you have a bad canopy, spend the time visually confirming that you have a good grip on your cutaway/deployment handle. Lastly, just because you have a MARD or RSL doesn't mean you should assume its going to work. Those are luxury items, and just like an AAD you should never assume its going to save you.