Lanark is not Glasgow.
... and I can assure you that Glaswegian (or Weegie) and the Lanarkshire Dialect are two completely different animals. Lanark is after all 30 miles from Glasgow. Infact, in Lanarkshire, which stretches from Harthope in the south to Carron Bridge in the north (a distance of around 60 miles), the people of one area struggle to understand the others. I live in Wishaw, which is about midway across the county, and I genuinely struggle to understand some people from Kilsyth, which is in the north.
As Lanarkshire is placed midway between Glasgow and Edinburgh (Lanark especially), it takes a selection of both to make its own unique local twang.
Although, I do agree one thing, and I say this as someone who was born there (as it was where the hospital was) and works there. The good citizens of Lanark are usually incomprehensible due to either their low selection of genes, heroine addictions or love of Buckfast wine.
"Gonnae gie us a pound mate, so ah can get the bus tae Hamilton tae see ma bairn, ken? Cos ah wiz it the soshal an they'll no gie us f**k aw, cos they sed ah need tae fun a joab!"
I doubt the Sherrif of Lanark was murdered by William Wallace, he probably commited suicide after realising he could never match him linguistically.