Renaming boats / ships is a delicate subject!
Not wishing to boast or come over as a sea fairing macho man. Wether on a boat or a ship a sailor does become attached to their vessel. Especially when she is battling through seas that no sound person would be out in, ... as she heels over, the thought is, will she become upright again! Fact is she does. At these times all on board sings the vessels praises and a fondness for the old girl is born!
Yes i know those are extremes at sea and not the canals,however that is where customs and sayings are born. we are at the end of the day a sea going nation.
The other reason i know harks back to sailing ships and piracy. The ships name was carved into the keel, when the ship was taken the name was carved out thus rendering a weak spot in the keel. How true it is who knows but its a good ditty!
Worst sea i was ever in was the north sea on the HMS Hermes. We had green water over the flight deck. Allthough she was sold to Pakistan Navy, she will always be the Hermes to me
Shaun