"No, it's less effort than that"

He wants to present a low number, to encourage whoever he's dealing with on his end to do what he wants, gaining the benefit from that.

So he'll use every technique under the sun to encourage devs to give him a number he likes more, while never making it look like an order or coercion (which would make it his number - spoiling the whole play).

But when it inevitably takes much longer, he can point at the numbers the devs provided and say he was just communicating what they told him, so he's not responsible.

The only language these types understand is for requests for estimates to be "reviewed" to result in them always going up, to send a message.