I think if you factor in the Celtics schedule, going 8-4 might be more impressive than people realize. Food for thought, from November 4th - November 24th:

• Celtics played 12 games in those 20 days. More than anyone else in the NBA. This means that the Celtics played a game very other day, with 2 B2B’s thrown in, (one of the B2B’s being on the road)
• 8 of those 12 games were on the road. Tied for the most road games of any team in that timespan
• 6 of those 12 games came against opponents who are top 10 in NertRtg in that timespan

3 of our 4 losses have come on the road against top defenses and 3 of our 4 losses were by a combined 3 points in regulation. We went 4-4 on the road and undefeated at home. We only lost 1 game with our starters, which was a 3 point loss where the starters were a +16 in 15 minutes.

Obviously you wish they won more, heck even just one of those overtime games would have been great. But given the context of the schedule, a 54-win pace kind of seems impressive.

TL;DR: Celtics just ran a gauntlet and coming out 8-4 is probably more impressive than you would think given the schedule.