I can agree with this statement. I also disagree with trying to change to a different frequency right in the middle of things. I would personally suggest using channel 8 with no code for everything, lock coordination, passing, hazards in the canal and what not. That way everybody in range hears what is going on and can make plans accordingly. As soon as you add frequency jumps into the mix with untrained radio operators you are asking for trouble. If you want to simply chat with someone, I.E. talk about sports, the weather, or that strange growth on the back of your leg, you then move over to whatever frequency suits your fancy. this is what PMR446 is there for.
Basically this is not a proffessional radio service, and the people that have the most to gain from using it are far from proffesionaly trained, therefore follow the KISS principal. Keep It Simple, Stupid!