I got NBA League Pass for my birthday and have enjoyed being able to watch the Celtics much more often this year than before (we cut the cord on cable when we moved house, so I'm still subject to ESPN/TNT restrictions, but I grew up in the 70s when tape-delay was a thing; I'll cope). Even with the inconsistent play it has been refreshing to watch the Celtics two or three times a week and contrasting my direct observations with reporting and the blogospher.
When it comes to the Celtics offense for example, the eye test really tells you what you need to know. Some simple things to watch for:
Walk, jog, or sprint? How quickly do they get it across midcourt and when? They don't always need to sprint, but pretty much any time the ball is stuck in Walk, it will be a possession that ends with a poor shot. The best candidates for Sprinters should be Schröder, Smart, and Pritchard because they have the best handles, but rarely do they sprint. I think in part because they don't want to show up two of the frequent joggers, Tatum and Brown. To which I say: screw that, sprint downcourt and pull the ball back out if you are in a 1-on-3, but don't wait for your teammates to run. Hell, Al and Rob Will will sprint when they get the chance. Reward them.
Pass or pound? Another simple visual to check is what's the ball doing once it comes across half-court? Are we trying to nail down a loose piece of the parquet 30 feet from the rim or is the ball moving from player to player to find or create an open shot? Heck, just count how many passes are made before the shot goes off. The more passes, usually the better result.
And along those same passing lines, ask yourself post or perimeter? The more the ball goes down into the paint, usually the better the result for the Celtics. Yes, they can still get open shots by swinging the ball around the perimeter, but the more it can go down rather than just around, the better the result for the men in green.
Finally, take your eye off the ballhandler and watch for player movement. Are guys being active without the ball or are they camping for a jump shot at three-point range? Ball movement can create open space for good shots, but so does having people running and cutting. Don't beliee me? Go find old footage of John Havlicek; it's not like he had a career or anything.
Have fun watching the Celtics even if it isn't always fun watching the Celtics!