Useless child seats?

Following correspondence with the Mercedes online customer helpdesk, I have established the following facts about the two additional rear-facing seats in a Mercedes E Class estate:

1. that they cannot be used for children over 140cm in height or 40kg in weight
2. that Mercedes do not recommend using any kind of booster/child seat in the rear-facing seats
3. the law states that children under 135cm in height require a booster or child seat

So the unavoidable conclusion is that the seats are only suitable for children above 135cm and below 140cm in height. Surely that can't be right? What would be the point in Mercedes going to all the trouble of creating and selling this extra feature for the brief period during which a purchaser's children might be in that tiny window of height range?

I suspect that the Mercedes helpdesk is just being lazy or uninformed - I will forward the email chain if required - but I know of no better authority to ask. Can you shed any light on this please?

Asked on 19 June 2011 by David C Sheasby

Answered by Honest John
It might be that, because the seats are already designed to be child seats in the same way as the built-in child seats in some Volvos, Sharans and Alhambras, no booster is required.
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