The best strategy for making a left hand turn across three lanes of traffic when there is no light. Slowly crawl out into traffic blocking it, eventually the driver will be able to slowly cross all lanes of traffic. Oncoming drivers will stop to forgo impending damage to their own cars.
This strategy can also be applied to more or less lanes of traffic, making it a very flexible method of getting to a destination.
Titled Boston crawl specifically because the only way to cross traffic in Boston is to block the way of other drivers. There is no way more than one person in unison will let a driver into traffic.
To make a left hand turn onto Beacon street, you will probably have to do the Boston crawl.