Doesn't look like it, but one thing that has me confused is the SK you couldnt town portal during the boss fight could you.
I don't think you can, no. But if you could, would you really want to? TPs don't function like they did in D2, where you would would summon the portal and you would have the choice to go through it or not. In D3 you're transported to town directly, meaning you'll miss out on the good stuff while you're away.
Besides, what you really wanted in D2 was a way for you to quickly get your body back in case you died, and as someone already said, the banners now serve that purpose in D3.