Jessica Wildfire makes another observation I'd like to comment on as a finale to this series on her article. A boyfriend once asked her to "watch him jerk off. Not in a Louis CK creepy kind of way." She states she kind of regrets not relaxing into it more.
She's right. She could've learned much sooner that when a man is in a relationship, he still masturbates. It's because he wants to relax into himself, enjoy the journey without any real end goal in mind. Yes, chances are he's going to cum, but when the activity begins that isn't on his mind.
When a guy asks his partner to watch, sure it's a bit of exhibitionism at work, but it's also a way to teach. If Jessica had watched, she would've learned the fine art of the hand job specifically for him; how he likes his cock stroked, his balls massaged, or his nipples played with. Perhaps he likes internal or external prostate stimulation. Learning what a partner likes, what he (or she) wants and how to go about it can foster better sex.
It's a long, slow and luxurious thing which ends in an explosive, satisfying ejaculation.
Now, whichever the case, you've got all weekend to teach or learn.