hrothgar, on 2021-June-23, 04:49, said:
If you go further back in time, you have structures like Gladiator that uses 2♣ as a puppet to 2♦
One can also play 2♧ as a marionette to 2◇, to be broken only when opener holds a 5-card major (as in early 'Puppet' Stayman). This offers a fairly sure 2◇ even if responder lacks 3 card support for one or both majors.