Yes its true, we did not need any wedding-related document support for our Fiancee visa (except refering to our plans/ date in the letter of support), and we did not need an interview either.
It seems risky to book the reception if you cannot book the ceremony (which you can't by law until both of you are in UK), and if you don't know that the visa will be granted when you expect, if at all. We waited 16 weeks and others waited just 7 weeks, so fixing a wedding date is difficult until you get the visa.
Also I heard that some people who submitted catering bookings etc with their applications got into difficulties with the Embassy because of this (in one case getting their application rejected when the Embassy could not get in touch with the supplier).
Good luck on your application
