This is definitely bullshit. But it's bullshit that sounds like it's got some sort of basis in reality, so Strange nods. That does make sense. Steven's got some sort of magical barrier at the temple, doesn't he? That should keep out the leeches.

"Very well," Strange remarks, with a sigh. "But if I spot any leeches there, I'm burning the place to the ground."

The odd behavior continues as Strange just...stops moving for a moment. Instead of walking forward, letting Syrlya teleport him or anything like that, he bends down and places his fingers on the ground. "I'll permit you to accompany me," he says, before Strange starts to mutter a spell.