There are many similarities in coaching philosophy / style by both of them ... of all the coaches in the Boston area in my lifetime these two are the closest of all in their thought process IMO. So I am very sure they can relate to each other on a very high level as well as a personal just 2 guys level. First take all the pressure of coaching the sport ... then add in how hard it is to coach in this region where the fans are for the most part very sports educated compared to others around the country.
Not easy at all and yet these two seemed to be born to take the reigns of the job. Coaches are generally fired and they take their system elsewhere to try again. Belichick and Julien have the ability to change their team as they go ... no easy task. All that crap about Belichick being a defensive minded coach and out of nowhere we experienced the 2007 Patriots. Julien has begun a similar task here with the Bruins. Brad Stevens I am sure is learning from both of them.