I suppose the sensitive period for order is a theory without solid evidence to back it up, but I am a Montessori fan and it appeals to me--plus it allows me to blame my sometimes lack of orderliness on my mother missing the sensitive period wink

http://www.mchsf.com/blog/details/the_childs_sensitive_period_for_order/

I can see the wisdom in Nik's approach too, although I don't think I could do it...but for the OP maybe there is some middle ground that you could both live with.