Ulrich,
The nice thing about using up brownie points is that you can have the opportunity to build them back up again. Glad you will be joining.
Good question on the jacket and tie thing. When I invite guests personally it's never a requirement - I only wear a jacket and tie when there are group functions at the club.
That being said it depends on who you ask, we have no written rule. However, if the 50+ crowd have a golf day or interclub mixer here they always put on jacket and tie for dinner.
The inner circle (older classic clubs) in NL are different than the rest where you would only need a jacket & tie if you were there for a competition I believe.
I would say for our group it's looked positively upon but not required. I will most likely as host wear a jacket and tie myself, however I would not single out people that chose not to.
Sean, understand your points, would still hope you can make it. I wish it were as easy here as being able to arrange all the games in the weekend but honestly in the end I'm rather lucky to have been allowed an option at all.