George S. Ledyard
The question is, what is meant by serious intent. Are we talking about grabbing with the intent to restrain? Or are we talking about grabbing with the intention to off balance, neutralize any defense and deliver a secondary attack?
It means that whatever your intention is, you'd better not smile or laugh.
(Seriously, this is a good point. Knowing that someone has a "serious intent" doesn't tell you much, unless you know what they seriously intend to do.)