actions on multipe cards

[okken]

for example:
cards delete 1,2,3 - to delete cards with IDs 1,2,3
cards update -o okken 4,5,6 - assign owner okken to multiple cards
start and finish - should also accept lists if ids.

Question:
Should a "are you sure?" confirmation dialog happen? maybe
If so, should normal single item operations also have that? maybe