Abbreviations in the UK

Yes! This is what I remember being taught in school in 1960's England, both the indentation and all those full stops and commas.

Even in the 1950s (gack!) when I was corresponding with an English penfriend I was bemused by all the commas, especially after the street number.

Even in the 1950s (gack!) when I was corresponding with an English penfriend I was bemused by all the commas, especially after the street number.

Looking at it now, it seems silly doesn't it? I kind of like the open style in use these days. I hadn't realized how much things had changed even in my own usage (I would never dream of writing an address that way anymore for at least the last twenty-five years!) -- it's amazing how we all adapt via a kind of osmosis.

I think there is a balance which has been overstepped somewhat today.  I may not use the old indetated and fully punctuated address style of the past, but I do always include appropriate periods after initials and abbreviations, viz. -

Mr. J. Smith
23 Acacia Ave.
Somewhereton
Anywhereshire

The "open punctuation" style which seemed to become popular very suddenly was a much bigger and sudden change in my opinion, and the complete omission of punctuation in the salutation and close of a letter is something I dislike intensely. 

The "open punctuation" style which seemed to become popular very suddenly was a much bigger and sudden change in my opinion, and the complete omission of punctuation in the salutation and close of a letter is something I dislike intensely. 

I would never not use punctuation there    I do tend to write things out in full ("Street", etc. rather than "St.") at least in a formal business letter.

I would never not use punctuation there   

Neither would I, but that seems to be the suggested style from many quarters in Britain these days.  I think it looks cheap and nasty, as though the writer didn't have any idea how to punctuate properly so he just left it out completely. 

I think there is a balance which has been overstepped somewhat today.

... and possibly a tendency to mix metaphors as well?

... and possibly a tendency to mix metaphors as well?

But at least they'll be well-punctuated mixed metaphors.