That's odd..I had a full body BSE on my iPhone 5 and I was still able to use my Spigen Neo Hybrid over it.
further update. i got the case back on. the mistake i made was trying to put the plastic part over the tpu from the front towards the back rather than the reverse. the front part seems to stick out a little further than the back part and makes it harder if not impossible to do it that way. this whole 8.0.1 dead phone thing has me flustered. case fits. very very snug but it fits. looks good. still not happy with how the bse went on this time but at least the phone is well protected for the moment.