I'm not quite grokking the intent of the statement. What's the difference in impulse between a push and a shove?

I believe the quote is from The Rolling Stones when one of the twins were getting impatient about recovering their bikes that they had abandoned when they matched with the Wargod and suggested that they give them another pull. Actually, I never quite understood it myself why you couldn't stop it with a shove. It might have to do with the catcher not being able match the center of gravity to stop it without causing it to spin.

The ABC series Defying Gravity used the exact sequence a couple of episodes ago when the physicist shoved a large cargo packet at the Venus Lander pilot and amputated her finger. In this case, she didn't see it and didn't attempt to stop it as far as I could tell.

In the case of the mass of bikes, the tugs would be additive. One tug = stop with more or less equal force. Two tugs = twice the force to stop it. Etc.

I could see where two or three hard tugs could create a momentum far harder to stop than the perpetrator might think. It's a case where the character is fooled by how the mass would behave if it were, say, a rolling cart on a planet surface. Newton's law, etc.

Pretty slick example, but it does require some thought and basic physics to unravel.

I was going to bring up Defying Gravity, too -- what a weird show!

Sounds like it's assumed that a shove would just angle the item in some other direction rather than stopping it.