Well i would not want to dampen any hopes because i too am impatient for humans to start getting serious about interstellar space. The problem is until we make some big advances we remain far too succeptible to catastrophes.

I think Gourhead's ideas are great for building ourselves into a civilisation technologically powerful enough to accomplish interstellar flight, but I do think the propulsion technology will be difficult to time becuase in some ways we dont even know what is possible, or whether there is some great new technology around the corner which would completely transform the challenge. Remember we are humans, and one can imagine the problems there will be in future getting funding for these types of programs, unless its sold to the public as clean energy..for instance.

This kind of program will be swamped by petty politics and dogma - unfortunately.