Maybe but I don’t know the details.
However, if water is being used as a propelant, you probably don’t want to use it as a radiation shield since you would be consuming it.
The way the article is written, it seems like the guy promoting the idea is saying, “We still have bugs to work out, but all we need is money from somewhere . . .”
From what little searching I did, this seems to be the method of choice -
http://www.nasa.gov/vision/space/travelinginspace/future_propulsion.html