"Just as a side question: Do Scottish newspapers print stories using broad Scots dialect, similar to how a few folks post? Are modern books printed like Burns would have spoken? I never understood how this works."
Bill, please don't confuse accent or dialect with grammar. It used to be said, that the best English in the UK, was spoken in Inverness.
By that they meant grammatical English, as they do have their own particular accent in Inverness.
What I take from Miss Thompson's comments is this. If you speak gangsta with your friends, that's quaint but OK, if you go for a job interbview and still speak gangsta, you're an eedjit.
A couple of comments from other sources, re the Scots versus English dialect.

THROW THE R AWAY - The Proclaimers

I've been so sad
Since you said my accent was bad
He's worn a frown
This Caledonian clown

Some days I stand
On your green and pleasant land
How dare I show face
When my diction is such a disgrace

You say that if I want to get ahead
The language I use should be left for dead
It doesn't please your ear
And though you tell it like a leg-pull
It seems your still full of John Bull
You just REFUSE to hear

Oh what can I do
To be understood by you
Perhaps for some money
I could talk like a bee dripping honey.

I'm just going to have to learn to hesitate
To make sure my words
On your Saxon ears don't grate
But I wouldn't know a single word to say
If I flattened all the vowels
And threw the 'R' away
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Listen Tae The Teacher

Nancy Nicholson

He's 5 year auld, he's aff tae school
Fairmer's bairn wi a pencil and a rule
His teacher scoffs when he says "hoose"
"The word is house, you silly little goose"
He tells his ma when he gets back
He saa a mouse in an auld cairt track
His faither laughs fae the stackyard dyke
"Yon's a MOOSE ye daft wee tyke"

chorus:

Listen tae the teacher, dinna say dinna
Listen tae the teacher, dinna say hoose
Listen tae the teacher, ye canna say maunna
Listen tae the teacher, ye maunna say moose

He bit his lip an shut his mooth
Which one could he trust for truth
He took his burden o'er the hill
Tae auld grey Geordie o' the mill
"An did they mock thee for thy tongue
Wi them sae auld and you sae young?
They werena makin a fool o' ye
They were makin a fool o' themsels ye see"

Say hoose tae the faither, house tae the teacher
Moose tae the fairmer, mouse tae the preacher
When yer young it's weel for you
Tae dae in Rome as Romans do
But when ye grow an ye are auld
Ye needna dae as ye are tauld
Don't trim yer tongue tae suit yon dame
That scorns the language o' her hame

Then teacher thocht that he was fine
He kept in step, he stayed in line
Faither says that he was gran'
He spoke his ain tongue like a man
An when he grew and made his choice
He chose his Scots, his native voice
And I charge ye tae dae likewise
Spurn yon pair misguided cries
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

THE NEW TEACHER
(Written by Jim Douglas)

chorus: Now is a Dove a Doo Dad?
Is a Doo a Dove?
And is a cow a coo Dad?
A sparrow jist a spyug?
And is a wall a wa' Dad?
Is a dog a dug?
She's gawn tae warm ma ear Dad
Instead o' skelp ma lug.

Oor new teacher's awfi posh Dad
She chinges aw oor names
Oor Shuggie is now 'Hugh' Dad
And Jimmy's always 'James'
'Am puzzled wi' it a' Dad
Tae why she shoogles words
Ans ah must be glaekit no' tae ken
That feathered friends are 'burds'

chorus.

Now there's twa words for everything
They're shoogled in ma heid
How can I be well bred Dad
When ah keep sayin' 'breed'
Now is a crow a 'craw' Dad?
Is a bull a 'buul'?
A'm goin' tae try ma best Dad
Ah wuull, ah wuull, ah wuull.

chorus.

Well ye've taught me aw wrong Dad
Ye call a ball a 'baw'
Yer wife is now my mother Dad
Ye said she wiz ma maw
It fairly maks me scunnered
Ah'll never pass ma test
A'm no sure whit a'm wearing noo - a semmet or a vest.

chorus
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

However, all that proves is, dialect and grammar, ar two different things.