you drag a flow element right on a sequence flow, and the sequence flow shows dotted borders to sybolise that it will accept the element and connects the new element.See the first 2 steps in my yesterday picture This happens right now
and this is not magic. What is the big difference to let the previous connections fall, only in the case that new connections have been etablished?
On the other hand, i have nothing against a special key to move connected flow elements on a different place. The modeler is really perfect in modelling from the scratch, and I love it to use on process discovery. Nevertheless, it is painful to swap/rearrange flow elements, and I would appreciate a solution like described. With or without any special key.
The situation you mentioned in your picture can be resolved similar to the deleting process: If you delete a flow element with an input and an output, situation is definite, so that you can join the previous flows together. With gateways you can decide to join the first incoming and outgoing flows in the XML If there are default paths, you could prefer them. For me this is not magic, just because you deal in a similar way in other situations.
And if the user has moved it unintentionally, she can always press ^Z.
But please realize that change