[pescetom]

"If you want to play weak jump shifts, you MUST create some vehicle that will allow responder to constructively drive the auction to the correct level/strain with a big hand. Weak jump shifts are used to destroy the opponents auction, not yours."
I would go even further... do not play weak jump shifts over a system that is not inherently compatible with them.



"Playing 1♦-2♠ as purely preemptive hinders constructive bidding."
A thoughtful comment followed, but I don't agree with this premise: hands suitable for a purely preemptive treatment are going nowhere anyway and this bid does a good job of hindering the opponent's constructive bidding.