Half Hour Late

A couple of weeks ago, I played with new member who shot an even par 72. We had fun during the round, so I asked him if he wanted to play next week.
 
He said: "Sure, but I might be a half hour late." 
 
The following week he shows up right on on time, and sets up on the first tee this time playing left- handed. Again he shoots a 72.I asked him if he wanted to play again next week. 
 
He replied: "Sure but I might be a half hour late."
 
I then asked him :"How come some times you play right- handed and other times, left-handed."
 
He said :"When I wake up in the morning and my wife is sleeping on her left side, I play left- handed and if she is on her right side, then I play right- handed."
 
I then ask ;"So,what if she is laying flat on her back?"
 
"That's when I'll be a half hour late!" he replied