When you are "parked" on the line you are unable to react in a prompt and seamanlike manner. You have to be aware that another boat may establish rights over you and be you must be prepared to respond.
++1
exactly, by being completely parked you are putting yourself in a very vulnerable position, you should always have some sort of steerage (just pull your main in for a second and move. Get crew to keep an eye on boats looking like they are going to get the leeward hook on you during the start.
If your parked at the line with a hole bellow you, you have become the sheep, the wolves will have at you. You want to be the wolf at the start, not a sheep.
While I have your attention, whoever it is out there who thinks you can back up to the line when called over early, you have NO rights when doing so, please don't do this unless you are not in anyone's way (which, if you were over early, is highly unlikely).
