Welcome to the forums and glad you've started playing DDSCB.
"Yelling" at the ref sometimes will not result in a T, but the likelihood is far greater than if you "work" the ref. And if you "work" the ref TOO much, a T can result as well..so this is pretty much reflective of real life. Sometimes working (or even yelling) at the refs can reduce the number of fouls they call though...of course that's hard to really determine for sure. And sometimes getting a T can turn things around for how your team is playing.
With regard to motivating your players during the time outs: I think it is worth the effort. Yes, often you get the response that they aren't paying attention, but even then its possible that there is a positive effect. And when you play enough and motivate enough you will notice there are other responses as well from your players. I believe that motivation can at times improve how your players perform.
(And hey! ...by the way....being tuned out by your kids doesn't necessarily mean that they aren't actually hearing what you're saying (at times) and might modify what they do.

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