sonic, #55,
In FAA land, irrespective of who initiates a visual approach - need to see the airport, etc, there is no statement of change of responsibility for aircraft separation when flying an IFR flight plan.
Or does the FAA ‘visual approach’ imply visual separation; if so then all relevant aircraft positions should be notified, and those involved must be able to see each other and should manoeuvre to ensure no ACAS resolution conflict.
Gross assumptions all round.