BTW a TabBleed of > 5pt doesn’t really make sense. TabBleed only makes sense if you have crop marks turned on. And we allow a 5pt gap between the margin and the top and bottom crop marks. So if you cut outside of 5pt accuracy, you are going to see bits of the crop mark in your final output. So if a printer can’t cut accurate to 5pt (1.75mm) you are going to have problems elsewhere.
Typing that does feel a little draconian. But so far nobody has reported problems. If they do, then we can perhaps use the TabBleed to control the amount of gap between a cropmark and its target.