What would you think if you saw a tvc that was looped for an entire ad break?  
Eye-catching for sure, and definately expensive.  I couldn't name a brand that tried this tactic in the past, and maybe there's a good reason for that.  Scarcity creates value.  But if a bold brand did try this, what kind of message would this add value to?  Answer: a repetitive one.

And who better to champion this tactic than - Duracell?!

For the bunny - and now tv ad -  that keeps going.  It's Duracell batteries.  They last longer...