Is this actually a technique?

[Melf]

The other day, a fellow bassist and I were sitting in Guitar class at school. He was playing a Les Claypool solo and I asked him to show me the first part. Well he tried and there was this easy slap part that I just couldn't get right. So he says, no you're doing it wrong! And I hadn't noticed before, but he had his forearm vertical to the neck with the elbow almost touching the strap screw on the bottom. I tried it and I got the slap part but it didn't seem right to me. I kept thinking, how could you even do that playing standing up? Is this a usable technique or an odd innovation on his part?

[CS Bass]

No, it's an arm position. Use whatever is comfortable for you.

[Christopher]

Mark King plays like that: he tucks the bass under his armpit and slaps with his forearm parallel to the strings. Probably hard to do if you have a large-bodied instrument.