colregs, I think, ( please correct me if I am wrong) can give priority to a sailed dinghy over a supertanker, but like many HGV's they aint stopping for you cause they can't/wont or just plain can't see you!
I assumed he was a holiday maker killing time on the river partly because it was a small boat 25-30ft not a 50+ footer, hence the need to tell him why he should return the bridges.
That stretch of cannal is just far enough from Reading (a hire boat yard)for the novelty of moving bridges to wear off, so during the summer evey other week you can expect a crossing blocked
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