No, I don't think it's part of the standard. Here at our college, at least, we route TC separately from video and audio, either as part of the RS-422 signal or LTC distribution. The same has applied to rented OB trucks we've used in our productions.
Also, I can't remember TC being mentioned at all when we went through the SDI signal in our classes last year. But that might just be my memory failing me :-) Actually, I haven't heard of SDI carrying TC at all.. But if there in fact is a more or less standardized way to do it, I'd love to hear about it :-)