But there is one area where progress really seems feasible within a few years: radical life extension. The right combination of drugs affecting gene expression just might do it.

You will probably not get radical life extension by solely altering gene expression. You'll need something more invasive.

and making sure that the path is clear to extending healthy life, not decrepitude.

You know that is in fact the current state of medicine, e.i. extending life a little, but not really increasing healthy years. For example warfarin (commonly subscribed to elderly at greater risk of cardiovascular disease and stroke), do not improve quality of life, more the opposite, since it reduces clothing --> increase bleeding, cause spontaneous bruising. I'm all for healthy lifespan, but that is what I'm hoping initiatives like SENS might deliver as well as increase in lifespan.