LE Cast spells with shield equipped

[essexfuzz]

Kind of self explanatory. I would love the ability to keep a sword in one hand, my shield in the other hand, and still be able to cast a spell. The way I see this working is clicking either of the mouse buttons individually uses the corresponding hand (e.g. slash or block) but if you click both mouse buttons together it casts the equipped spell. Not sure if this is possible, just something I'd love to see.

Thanks