I've experienced good Guards and bad Guards with this scenario. A good Guard (in my opinion) will try the cab to cab once. Then, walk through the train, knock quietly on the door and then quietly enter, waiting for the Driver to tell them any information.
As for the bad Guards, they have interfered with safety critical conversations between me and Signallers (including one occasion when I was in the middle of an emergency call to the Signaller).
The assistance of a professional Guard is worth its weight in gold, interference isn't (and that goes for any members of staff who happen to be passing on the train that go to assist).
Thankfully, most people have the common sense to do the right thing and it's greatly appreciated.
Yep, totally agree with the above.
I had a guard barge into the cab and ask “how far are we from station X?” when I was approaching a red signal a few weeks back. I couldn’t believe it. I didn’t make a big deal of it, but should probably have said something to him, in hindsight.
Most are far more sensible. If the brakes go on their first thought won’t be a welfare issue (obviously that would change if I didn’t contact them within a few minutes).
The most recent example I had was a signal going back on me. Dropped the lot, spoke to the bobby first, for obvious reasons and then called the guard within a couple of minutes. He had, quite sensibly, given me the breathing space to have the necessary chat with the signaller.
I’d have no issue at all with the guard discretely entering the cab while I’m on the phone to the signaller.
EDIT: and no issue with the guard, or especially the attractive customer host, coming into the cab when the train is moving to give me the breakfast they’ve just made for me

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