"There is actually a profound difference. Saying vote Labour effectively blocks forming a united front with people who are LibDem, Green, Respect or any other party voters, it also doesn't cut much ice with people who are staging a protest vote against the mainstream parties."
Notice the key word "who are LibDem voters"!
I was talking about people at the grassroots. Say Griffin was staging a meeting in my town, and we wanted to physically break it up - it's possible that many w/c people who didn't consider themselves socialists but had an abhorrence of racism might want to join the demo. If we adjusted our tactics to keep liberals and vicars onboard it might be a popular front - but that wasn't what I was getting at.
If the BNP were standing in a council ward and we wanted to do a mass leafleting to say that they are Nazis, once again there might be people who were not socialists involved in the campaign.
Strange for me to talk about "not cutting ice with people who are staging a protest vote against the mainstream parties" if I thought that it was these mainstream parties who would be at the heart of the united front.
But evidently, Butchers and Belboid know more about my politics than I do!
You obviously don't have much confidence in arguing your politics, as you believe they must be hermettically sealed from those who might disagree with you. Try working alongside people and winning them through debate, argument and practise.