Does anyone else remember 'back-slang'?

Yes, I remember back-slang. I had an uncle who "spoke" it.

My parents too had the annoying habit of spelling things they didn't want me to hear. That stopped very soon after I started school, as it only took me a month to learn the alphabet.

mention of bona reminded me of those wonderful radio shows, round the horn etc. now on radio 4 extra.
i'm so dopey that it's only in the last few years that i've realised the double entendre of bona.

SiL used butchers’ slang in East London in a recent job. It’s still very much alive and kicking!

I found writing and reading it quite difficult, Smileless

I must practise speaking it (I've no-one to practise with, though).

I can still speak it quite fast Callistemon; a lot faster than I can write it

Like you lemongrove never heard of it called that ,but remember Stanley unwin well I just thought of it as googledegook
I remembered words being spelt out by the family when I was small and dad or granddad would say they were ‘going to see a man about a dog‘ when they were going to the pub

Smileless2012

aygo yegas b1zzle maygy graygan aygand hayger saygistagers yaygused taygo taygalk baykgakslaygang waygan theygan wergan gaygirls.

Maygy braygothayger aygan aygI daygid thayge saygem waygen wayger chayldrigayden.

Translation:
'Oh yes b1zzle my gran and her sisters used to talk backslang when they were girls.

My brother and I did the same when we were children.'

It's a lot harder to write it then it is to say it and my gran's version does look very similar to your parents.

Yes, we used to use that system at school, Smileless

However, we called it Dog Latin and could speak it very fast.

(wayge waygere paygosh!)

Yes, I remember back-slang, sometimes called 'pig latin' and I don't think it was anything to do with Cockney. We also used a bit of Romani, from one grandfather, and bookees' slang from the other grandfather. I could do 'tic-tac' as well, but can only remember the 'evens' sign now.
My dad used the occasional polami word, that he picked up during WW2, and up to his death would give assent to something by saying 'bona'.
When my kids were teenagers, French kids were using 'verslen' a sort of backslang in which syllables were just reversed.
My DH hates any of these odd languages, and so I found myself dropping them around him, and only occasionally now use them with a few of my family. I still use a few of my native dialect words though.

Nope, never even heard of the words back slang.
I remember Stanley Unwin though, with all the gobbledygook.Was that it? Why on earth did people go to such lengths to hide a bit of conversation?We were just told to leave the room if adults wanted to talk without us knowing the subject.

Yes, I remember backslang although I could not speak it. I thought it was a London thing, something the Covent Garden and Billingsgate porters used. Nothing to do with Cockney rhyming slang. Was backslang what Stanley Unwin used? If so, I didn't realise that. My parents used French if they didn't want my sister and I to understand but when we learned French at school we quickly outstripped their own knowledge so that little ploy didn't work any more! DH and I used to spell out the words we didn't want the children to understand but that didn't last long either as they were not very old before they caught on.

aygo yegas b1zzle maygy graygan aygand hayger saygistagers yaygused taygo taygalk baykgakslaygang waygan theygan wergan gaygirls.

Maygy braygothayger aygan aygI daygid thayge saygem waygen wayger chayldrigayden.

Translation:
'Oh yes b1zzle my gran and her sisters used to talk backslang when they were girls.

My brother and I did the same when we were children.'

It's a lot harder to write it then it is to say it and my gran's version does look very similar to your parents.

remember polari, with kenneth williams etc.
my mother used to speak with her sister of the p.u.b., spelling out the word, when i was v young presumably because she did not want me mentioning the pub to others, in case it gave the wrong impression.
but what if i had repeated as i heard, the p.u.b., as most people would be able to spell even if i couldn't.
my brother and i still sometimes refer to a p.u.b.

My parents would discuss matters not appropriate for my ears in Italian. It would automatically make me tune in to attempt to work out what they were talking about. I became pretty good at it. ?

When DH worked for an abattoir in Cornwall he used to make deliveries of Woc to the Indian restaurants. All their menus advertised Beef curries and it would never have done for customers realise they were actually eating elderly cows.

Yes. I could never do it but my two sisters were brilliant at it.

How weird, a friend of mine only mentioned this a couple of days ok..hadn’t thought about it for years! My Mum and Dad did the same, but I picked it up.....

Yes! My brothers talked that way thinking I couldn't understand them, but I could. Easily.

Oh yes! My dad knew some, from when he worked in grocers or delis in the 50s.
E.g., taf was fat, dlo was old, and a rat was a Jack tar. This was all so the customers couldn’t understand.
This was in London, by the way.

ExD

Yes there was a bloke on tv specialised in it - it was possible to understand him if you listened carefully and unless the children were very young I think they'd have caught-on quite quickly.

Oh, was that Stanley Unwin?

Always thought what a twit he sounded.

My parents used to spell things out to each other knowing full well that my skills were not far developed enough to be able to understand what words they meant. This with various slang terms for adult chat such as ‘Family way‘ ‘Funny Business’ and various bits of Cockney slang from an old great uncle who worked as a London fireman during the Second World War, and it was easy for them to have a conversation that l did not know the meaning of!

Yes there was a bloke on tv specialised in it - it was possible to understand him if you listened carefully and unless the children were very young I think they'd have caught-on quite quickly.

I couldn't speak it and in fact can hardly understand what you have written - shall we go to the fair tonight? ....is it.

But I remember my eldest daughter, who is now 41, speaking it with her friends.