When to descent...

[Broomstick Flier]

Hi chaps,

I recently transitioned to the RHS of a CJ3, and the training capt. taught me the following technic:

While under vectors, but with a STAR loaded into the FMC and VNAV armed, and instructed to perform a descent, lets say from FL080 to 6000ft I should not descent immediately after receiving the ATC instruction, but put 6000ft on the altitude selector and wait for the VNAV path to be intercepted and let the aircraft descent by itself.

I think that somewhat odd, as I would descent immediately (is this not what ATC expect me to do?) and that was the way I made it on my previous type, where I flew single pilot. Is this acceptable, especially from an ATC point of view?

Thanks!