Esoteric G-ORb Master Clocks in general

I have been reading about the effects of an external clock and it has me wondering. The goal of the clock is to get the Transport and DAC working together. This will reduce clock jitter. My question is wouldn't it be better to have the transport sync with the clock in the DAC instead?

PS. I am not saying the Esoteric units aren't any good or anything like that. I'm sure they are wonderful.
The external clocks offer much higher precision than the clock found in the DAC (at least for Estoeric units).
The P5/D5 combo does offer you the option of using the DAC's clock, but as Tboooe correctly pointed out, their master clocks have much lower jitter which according to one user, was clearly audible.
dCS contends that their external clock is superior to slaving the transport to the DAC clock as master for lowering jitter.

While one would expect a company which has a $10k external clock to contend such, others have told me the improvement (with dCS gear at least) is quite audible.

Antelope Audio has a temperature controlled crystal oscillator external clock for about $1400 which is much cheaper than Esoteric's or dCS' offerings. I've not read of anyone using it outside of studios, though.

I've read that clock stability and jitter reduction "processing" are more important than clock accuracy. The Rb oscillators, at least by literature, are both very stable and accurate. The jitter reduction schemes seem to be proprietary DSP-based animals and surely impossible to directly compare as entities separate from the rest of the unit (oscillator, etc).

Seems, like many other things audio, you pays yer money and let your ears judge.
It just seems that having the transport clock to the DAC would be the perfect thing since the idea of jitter is to have both units working together. But like everything else we must use our ears and let them decide.