Post Dawnguard Download.

Ok.

If I save in the sneak position (including autosave) the reload registers my character crouched as being in sneak mode but not actually sneaking. I am unable to get out of it, meaning I'm in the crouched position yet clearly visible to npc's/monsters.

This disables sneak attack bonuses, yet retains the slow basic melee attacks while crouched and also disables mobility (forward roll etc).

I'm currently saved in a room with a Master Vampire and his thralled Giant Frost Spider.