Charlie Watts wears Keydge. That is when he is not wearing his Savile Row trash.

Here's a thought. Keydge make a sack jacket that is essentially work wear and is worn out of that context as a smart casual jacket.

It's not 'other'. It's the most authentic sack jacket available today.

He needs two sizes off the chest and shoulder minimum. But the length, button stance, arm holes will be all out of wack by that point.

That jacket is an overall.

Construction wise it's probably pretty much the same as a Keydge though. Mr Keydge must make a killing on every jacket sold. Laughing all the way to Le Banque.

This debate is going to run and run and run. I personally love my Keydge, is it Ivy? Probably not.
Someone far wiser than me once said on here that a J Keydge has its own little category and that sits well with me.
It is clearly related to workwear items but come on a fucking dust coat that a removal man wears? Get real.
Bop is right the lapels are wide and this is something that has bothered me a little but will not stop me from wearing mine.
It has its place in my wardrobe.

No.

It's an 'Ivy' 'Slack' jacket - It says so.

And what the hell is one of those  ?

It's a Keydge.

I renounce both the names 'Ivy' & 'Slack' - Pure invention.

It's jacket shaped, but does that make it a jacket in the accepted sense ?

By that reasoning a small dog is a cat.