[Bertie is silent for several seconds before deciding that 'the Joker' might need a little time with his own thoughts to everything out.]

Ahah! Hah... I s-suppose a chappie named 'Joker' would know best. I'll just, um... leave you to it, then. Tinkerty tonk!

[He's hanging up now... and might avoid picking up in the first place, in future.]