Riding a binding that is a squeeze is possible, but its far from optimal. Bindings like boards have a sweet spot for the straps and the heel cup / gas pedal. With a big size 11 on a M cartel you are pretty much maxing it out and are out of the sweet spot for comfort and performance.
I ride cartels (L) with burton rulers 11 with the reduced footprint. They fit with ease and I sometimes swap boards for a few runs with my buddy who has M cartel bindings. Its doable but I certainly don't feel as comfortable or as good response.
With a size 11 boot you need to get something pretty slim and not bulky also with reduced footprint tech. Of course make sure it fits your foot too.
Next time you get binding get L. They hardly way any more and you'll be more comfortable IMO.
Cheers... Only reason i'm hesitant is because i've already bought them and can't really take them back.
The only option i really have is to take the boots back and look for one with a smaller footprint. Might look into that. hm...