Sorry but from a personal respect point of view, if I felt that in a dining room that I had to "totally" clear my nasal passages, and no matter how quietly or discrete that I thought I could do it, I would not inflict the procedure on my fellow diners? No way
In your head it may be subtle; then again it may be not. It’s like that moment in time around others and you can feel your belly rumble and you think, I can do a quiet one here and get away with it, no noise, no smell. Gamble or not?
But being on a dining table no-one worth having around you would take that chance, they would make an excuse and go to the rest room or elsewhere to sort,,, so it being your nose,,why think you can get it all out quietly and not have the stomachs of others around you getting the sensation or feeling as we say in Scotland of "the boak"
If I was eating and someone did that in front of me then I would be heaving, so now it's my fault as I've now been sick or boaking at the dinner table due to another’s actions..mm