This is a repost of my summary from the last thread. There have been a few more theories since then on the last few pages but I can't be bothered to updated it:
IS THIS A FAIR SUMMARY OF THE THEORIES SO FAR?
For context the posted "joke" is:
There once was a man called Boswell. For short they called him Bos, and he walked up the post office steps.'
Various Punctuation Variations
(some depend on the revised version posted by OP as the version written out by the best friend which had a second "and" in it.
- There once was a man called Boswelland Forshort.They called him "Bos!". And he walked up the post office steps.'
His name is Boswelland Forshort. They called him Bos and he walked off because he ignored them - it not being his name.
- There once was a man called Boswell Forshort. They called him "Bos!", and he walked up the post office steps.'
His name is Boswell Forshort. They called him Bos and he walked off because he ignored them - it not being his name.
- Thereonce was a man. Called Boswell for short. They called him "Bos!! and he walked up the post office steps.'
His name is Thereonce. He was known as Boswell for short. They called out to his "Bos" but he walked away it not being his name.
The four letters pun
4.There once was a man called Boswell. FOUR SHORT they called him Bos, and he walked up the post office steps.'
Bos is four letters short of Boswell.
In addition some theory about him getting more letters from the post office.
The Boscombe Down Theory
5.There once was a man called Boswell. For short they called him Bos, and he walked up the post office steps.' But did Boscombe Down?
@Pipnik's niche Wiltshire theory that the joke leads to an unspoken punchline
But did Boscombe Down?
(Its a military site in Wiltshire)
The Story Cut Short Theory
6.You expect you're going to hear a proper story but it's cut short. So
'There once was a man called Boswell.
For short: they called him Bos... And he walked up the post office steps'. I.e. They've missed out the whole story to cut it short and skip to the final sentence.
The Mornington Crescent Theory
- The joke is that there is no joke but you have to pretend there is and that it's funny.
The Designed to Provoke the question "What For?" Theory
- Listener asks "what for?" To lead to some response about the letters "W" "e" "l" "l".
An unidentified visual joke theory
- Based on the friend saying "it's better in person" a theory that this "joke" is like that game when you pass the scissors crossed or uncrossed by the "joke"/"secret" is not that the scissors are open or closed but that the person passing has their legs crossed or uncrossed.
Thus that the teller has to do or signal something that gives the "joke" an additional meaning that we do not have here.
General load of bollocks theory
- Total wind up by the friend based on fact no amount of googling gives any indication of any similar joke.
Is that everything? I gave up at about p. 20 and read the last page?