The way I see it, the only argument against this approach is say there is a count started when there is less than 10 seconds on the clock. Specifically, say 9.8s is on the clock.
Let's also say that you (or said official) is very consistent in their 10-second counts. IOW, they have already called 4 this game (or even 1 or more than 4), and I'll even say that they've called 2 on each team. In each case, the actual amount of time allowed for the ball to earn FC status before a violation was called was less than 10s, and around 9.1s. IOW, the covering official actually has a fast count.
In this case, the "5th" case, if you do not continue to "chop" 10-seconds as you have been doing, and call that same violation at 9.1s, then you are not being consistent, and IMHO, doing a disservice to the game.
No, I do understand that no two times will be exact, but it's important that they be consistent. If a 10-second count occurs earlier in the game with clearly only 9 seconds coming off the clock, then when 9.9s is on the clock, and you don't have a 10s violation, IMHO, the coach has reason to wonder about your consistency.
Edit: another argument is for definite knowledge of timing errors.
