A few years back I had to travel this way and it was horrendous. Leaving early is the key, but not everyone can do that - have to drop kids at school or whatever. It is worth exploring some back routes to whichever part of the city you need to get to. Maybe you can get on a bit later and miss some of the stop -start. I eventually managed to get on at Charles St, because I had to get through the city to work in the south. Saved a lot of time for me and once you are throught the city it is a bit easier as well. But, the train could be a good option - lots of people are so used to just driving, we don't give it a second thought.
Depends on time of day of course but if you leave home at 7.00am you should get a good run into town barring any traffic accidents. It's takes about 20 minutes depending on which part of town. There's always the train of course which is really good. Catch the express and be there in 10 minutes but make sure you get to the train station early enough to secure a parking spot if you are driving there.