Comment 6 for bug 728081

The shortcut as currently implemented IMHO has one big caveat users need to be made aware off: if the current drawing level is inside a group, the parent group instead of the parent layer is actually locked/hidden. If the user then leaves the group (e.g. by clicking on a different object outside the group, it is difficult to unlock (or unhide) that specific group.

The only indication that this going to happens is the "Layer" selector in the status bar which displays the current drawing level (i.e. the id of the group which is going to be (un)locked or (un)hidden).

Related reports (the issue is not new):
Bug #863974 "elements no longer available for selection"
Bug #845844 "Groups not selectable - turned insensitive (locked) without using object properties dialog"
Bug #304251 "incorrect locking/unlocking -- unlocking the layer locks the group which was choosen to be active"