Hi Jon
I can relate to that article.
On many occasions I've lacked the courage to evangelise only to later feel guilty.
I'm now of the opinion that we know in our hearts the people God wants us to talk to about the Gospel. We must trust Christ and obey the Master. It's one of the greatest joys of being a Christian when we spread the faith and He's there with us (He has to be or else we're wasting our time). What a privilege.
It's all part of spiritual growth though. I have reservations about evangelizing for the sake of evangelizing. Taken to the extreme, we would feel guilty about not evangelizing 24/7. We must allow the Spirit to work in us and follow His lead. He will give us the courage, power and direction to evangelize effectively. In our own strength we are nothing.
David