God, these irresponsible myths!
Put your schools down in the exact order that you prefer them.
Each school looks at all the applications, they don't know who put them first, who last, they look at them all and judge them all against their published admissions criteria, and give the LA a list, in order, as to how each applicant meets the criteria and whether they can be offered a place.
If more than one school can offer you a place, the LA allocates you the school which is highest up your list.
If none of the schools on your list can give you a place (i.e possibly your preferred school if you are unlucky) then once all the other applicants have been allocated their places , the LA looks to see what places in schools there are left and will allocate you one of those. It might be a school miles away and one that no-one wants!
If you get allocated your second choice, you will automatically go on the waiting list for your first choice, and if someone doesn't take up their place, (moved away, gone private, preferred another school...) then you will get that place as soon as you are next on the waiting list.
Use all your choices in order of preference.
Do not list one school repeatedly, in each position on the list.
These are stupid myths spread by people who have not studied the system.