Another UK point of view
I worked in the private sector for over 25 years (1 company) and found that when taking a vacation the only way to get away from work was to be a couple of thousand miles away with no mobile, blackberry etc. Lack of resource was a concern of mine but the response was no addition to head count and no overtime (unless you worked for nothing.)
Beware of taking sick leave due to stress or you may find that when the time for staff reductions come round you may find your name at the top of the list.