Potential summoning stone at the click of an item? Pocket Locks have always been a thought. A cool item to have, as it's incredibly practical.
As we know blizzard so well, they like adding things more accessible and fun to get, and that would be a very fun item indeed.
Is there a reason not to?
One could argue it will lose the need of a lock or its uniqueness.
But then they wouldnt be any different than the shamans and heroism, and many other classes' abilities that are now shared through others.
Naturaly, it won't be exactly as the lock's requirements.
I can only see it work where you need atleast 4/5 players to summon someone with a 30m-1h CD, and change the lock's to 2 players required to summon the summoning stone.