I disagree with iPooPoo ahem iBoomBoom and I use the spawn protection after an Rc to further my survival and gain the next kill streak, or to knife someone in the back (which is my favourite use for it). However, it royally pisses me off when it happens to me lol. Angus will testify that it is infuriating to get stabbed in the back, when you are in an area with one entry point that you are watching like a hawk! Or you go into a room and check all the corners and go to move on and then you get nailed by someone spawning behind you.
The solution would be to revert back to spawning at spawn with the full protection. No disadvantage is dealt, but more importantly, there is no advantage gained!