What's the rush?
It doesn't matter what factors are part of the speeding problem: bow design, swims length, canal width/depth di dah di dah di dah. These factors do not come into play if you are not speeding and we are still left with a group of people telling the 'whingers' to "Tie up your boat properly so I can flaunt the rules and hammer along the canal like I own it." The simple fact is that as well as tying up your boat securely being a good thing, let us not forget that 'slowing down past moored boats' is one of the rules!
In the rule book
I know it's tedious, with moored boats all over the canal, having to slow down and speed up all the time, but it is in the rule book. The point of having a rule book is so we all sing the same song to the same tune. We can have certain expectations of how people are going to behave so that we can all do our boating in harmony.
What I do find amazing is the speeding boaters who, giving no consideration to others while on the move, shout out at me to Slow Down when I have the temerity to pass them later at a my normal 'chug chug not in a hurry' speed.
People getting hurt
I don't want to promote the rule book as a military manual, but we cannot escape the fact that people are getting hurt as a direct result of speeding boats. I have witnessed on two occasions bloodied heads appearing out of side hatches and a number of my friends have scalded themselves when their boat has unexpectedly 'heaved' as some 'holier than thou' speeder hammered past.
Yes I know the old boaters used to speed from job to job, but we don't live in those times any more and our two hundred year old canal system is becoming very fragile.
What's the rush?