For Nick tis the incorrect use of apostrophes and grammar generally 
For JOM tis anything constructively incorrect according to the Bible of Road Resurfacing and Traffic Management 
For BM tis whether to flip or fin 
For Tipsy - tis anything Nick says  

For Steve ...mmmmmm could be he is the most tolerant one
For GM tis anything if he has not had the required vat of  strong enough coffee
For DS - tis nothing as he couldn't give a monkeys what us plebby peasants worry about