In my family we actively hate the phrase retard as my step son has Down Syndrome & it is nasty term occasionally used by thick people to describe my step son. Thankfully although still common place in the US, it appears to be in the decline here. The Guitard is clearly a play on that word. I've never publicly challenged anyone for choosing to use the word but I personally find it distasteful and wish people wouldn't use it. Banter can have it's place (I love a laugh and a joke with my friends) but banter can often be a polite phrase for bullying too. That's not the same thing.
It always used to be drummer jokes, it seems to have shifted to bass and onto other instruments. I respect all roles within a band but this is more to do with egos and people who don't live up to the role. Thankfully the guitarists in both my bands are class acts. I have worked with a couple of difficult singers in the past though.
[quote name='mikel' timestamp='1494339533' post='3295106']Thats why Billy Connelly starts his latest tour shows with "Shaking all over" For anyone who is not aware Billy has Parkinsons, amongst other things. He refuses to be beaten down by his illnesses so he laughs at them, to make them smaller and less threatening. It's what the Brits do.[/quote]
The difference is that Billy is taking ownership of his own condition and I agree that is the best of what Brits do. Laughing at easy targets though isn't (not that I'm suggesting that is what YOU are saying but I think this is where some tend to get it slightly wrong).