How can they not keep him? They had him making appearances all summer long.
I saw footage on TV & the Celtics site where he:
- Was at Canobie Lake Park with a foster kids at summer camp
- Opening ceremonies & playing with kids at a Celtics court
- At a Patriots game on the sidelines before a game, press pics snapping
Would be bad form to use him as the posterboy of your team for 3 months and then cut him
Good form or not, I doubt he makes the roster. He doesn't have very good basketball skills and his motor is suspect. After all this time, his best asset is still his height. That can be game-planned against by matching him up with an outside shooting big to bring him out of the paint.
Just a small quibble: It actually hasn't been much 'time'. Tacko Fall didn't really start playing basketball until he came over to the US in the middle of high school, around age 17.
Most kids getting a sniff at the NBA have been playing competitive basketball since they were in middle school. And critically, it's those early years where most get schooled in a lot of basic fundamentals. Tacko was sort of dropped into more competitive levels that simply assume you have all that already. He got by through all this so far based on, as you note, his height. But he's had to play a massive game of 'catch up' in regards to learning all the basics of basketball and wasn't really helped all that much by being in a NCAA program. The Celtics have been putting him through intensive fundamentals training.
In addition to his height, one advantage he has is that he's apparently extremely intelligent and the coaches all glow about how fast he picks things up. But he's going to need at least a little time (repetition) to make all those basics become natural.
Currently, technically, Fall is on the roster (non-guaranteed contract). I expect they won't cut him unless a compelling need for that roster spot arises. If they need it to do a trade later in the year they could always just cut him at that point. So I expect him to be on the roster when they open the season. However, I also expect him to spend most or all of the season in Portland.
The cost of keeping him is simply so tiny and the upside potential long term is high enough that it's really kind of a no-brainer. Just put him in Portland and see how he develops this year. Re-assess next Summer.