I must have used 20 or 30 pairs of power poles and have soldered every single one of them and inserted them all using the small instrument from behind approach - I have used a variety of cable sizes from the largest ones that just fit into the connector (when using a spare / replacement cable for 100W radio) to small ones for very low power requirements and have had no problem with the connections to any of them.
When in use they do not take much of a tug to disconnect one from another, but I have rarely had that happen unless I’ve managed to tread on the cable or get a cable tangled up in my feet.
Stewart