Rear facing seats for 4-6 year olds hang slightly off the edge of the back seat so that they can allow some leg room for the child between the child seat and the car seat. No need for children's legs to be poking out the back windscreen :)
Haha at the AP / ERF comment - this is so true! You absolutely have to take your own situation into account. Being black and white about RF/BF/whatever isn't useful to anybody. Just be sensible!
Also such black and white attitudes cause problems rather than persuading more people to give RF a go.
If someone is worried about receiving a lecture from a car seat support source/page/group etc, they may not seek advice about the use of their FF seat, which might mean they are using it incorrectly, or which FF seat to buy, leading them to buy a poor-performing one or one which is hard to fit correctly.
When people feel they have to justify their use of a FF seat they come out with all kinds of reasons (which might obviously be true in their individual situation) which can turn into general myths such as all DC prefer to FF, ERF seats are cramped, ERF seats are too expensive, don't fit in small cars/with tall drivers, ERF seats are complicated to use, etc. Which is a shame because then people look at these things and think oh ERF sounds complicated, hard, unpleasant, expensive. When it doesn't have to be any of those things.
There was a long running thread on Pistonheads about car seats - one bloke would say a couple of times there's no issue with FF, FF if you want to, RF is safer but nobody else gives a crap about what car seat you use so there's no need to justify it on here. And it seemed to generally be true! As in nobody was castigating each other. Why do we (mums) do this?? People leap on each other and say such ridiculous sentences which don't have any basis in fact.