Interesting discusssion, I would put completely the opposite emphahsis on my debrief to an LPC candidate; if you have been cleared for the approach (ILS or other), then all R/T calls are merely courtesy to help the controller keep his SA. They are totally secondary to the task of flying the correct profile and as such can wait until workload permits. Radar to the ILS this is usually as it happens, but in a procedural environment crews need to prioritise taking into accoutn their level of currency.
Particulalry relevant at the moment, I have done a lot more procedural stuff than normal recently as ATC units are short staffed. In addition to a sudden revivial in LPC/OPCs in the aircraft as we are unable to get crews to the sim. Interesting times!