I'm not so sure that noting the position of a comma in a grammatically incorrect sentence is all that enlightening.
Actually, it's two commas (I misquoted the first time, sorry).
A boat finishes when any part of her hull, or crew or equipment in normal position, crosses the finishing line...
The position of the commas separates the clause "or crew or equipment in normal position", meaning that "in normal position" does not apply to the "any part of her hull" clause. So, the hull may be in any position and still satisfy the definition of
finish.
Regards,
Eric
