I'm sorta gathering not many care one way or the the other that this has been changed
To point out exactly - thru the whole previous unity life a l. click or 2nd left click on a launcher icon would pull all windows from that window group to the spread (scale)
This has been changed to only pulling from the current workspace, now if you want to open a window whose group is on multiple workspaces you need to actually go to that workspace to open that particular window.
Personally think this is one of the dumbest design decisions yet.
(particularly in light of the fact that user set bindings for 'scale > Initiate window picker for window group' on all Ws's has been & continues to be broken
For the curious the bug report that set this in motion over a yr. ago
Edit: there is a method to get this function back in post 5, currently works on compiz < 0.9.7, as to the future don't know
So this is semi-solved pending setting initiate_all in 0.9.7 or a possible reconsideration of design