playing left handed or right handed

Four guys who worked together always golfed as a group at 7 a.m. Sunday. But one of them got transferred, and they were talking about trying to fill out the foursome.
A woman standing near the tee said, "Hey, I like to golf, can I join the group?"
They were hesitant but said she could come once to try it. She said "Good, I'll be there at 6:30 or quarter to seven."
She showed up right at 6:30, and wound up setting a course record with a 7-under-par round. The guys went nuts and everyone in the clubhouse congratulated her. Meanwhile, she was fun and pleasant the entire round. The guys happily invited her back the next week and she said "Sure, I'll be here at 6:30 or quarter to 7."
Again, she showed up at 6:30 Sunday morning. Only this time, she played left-handed, and matched her 7-under par score of the previous week. By now the guys were totally amazed, and they asked her to join the group for keeps.
They had a beer after their round, and one of the guys asked her, "how do you know if you're going to golf right-handed or left-handed?"
She said "That's easy. Before I leave for the golf course, I pull the covers off my husband, who sleeps in the nude. If his member is pointing to the right, I golf right-handed; if it's pointed to the left, I golf left-handed."
A guy asked "what if it's pointed straight up?"
She said "Then I'll be here at nine o'clock."