Thanks for all your comments -

From what you say I suspect a refusal and then an appeal are on their way, although I would hope (maybe naively) that they would look at the immigration rules that state if they feel a visa can be approved but that certain documents (like bank statements in a series) are missing then they should request these before refusal....Here's hoping.....

If anyone out there's had a refusal on the grounds of a missing document, how hard is it to submit an appeal and be granted it if you can provide the documents within a suitable timeframe??

Many thanks to you all.