Is it even possible to stay at 24k hp in DG gear ? Anyway check this video out http://youtu.be/3UugzdjgBkU?t=3m10s
.. this noob shadow is running 33k hp for F&S NiM .. at 3.20 he gets down to about 2k hp .. I d argue the additional 4-5k hp saved his life
Im just gonna say this.
if your running a tank that only has one tanking set of gear, and you decide to itemize correctly for high mitigation, if you die.... its because your healers arent paying attention. because although having that little more HP may be nice 10-20%of the time in endgame content, your gonna be incredibly stressing your healers in the other 90-80%of the content. there isnt a single fight in the entire game that hits hard/rapidly enough through mitigation to need to stack any more endurance than your gear comes with.
spoken from experience as i run a full mitigation shadow tank and have cleared all content with ease often while only having one of our main healers and dragging along a second that we are trying to get some experience for.
in the end its all your preference but the facts remain; you may be granting yourself a small buffer on certain fights by stacking endurance but you'll be crushing your healers for the rest.
i can speak from experience on that subject as well on account that i play a commando healer that i have also cleared all content on. and healing a 24-26k shadow tank is much more easy to heal than a shadow running 31K. (I have had a situation once when that was the case)