Boot camp with external dvd drive

yes, there is a way, I remember doing this when I swapped my Superdrive for a disk drive while my old Macbook was not able to boot Windows from USB.

you need vmware Fusion and rEFInd installed

it's a bit tricky because non-apple USB drives are not working when booting the OS but this one works if you read carefully. basically the process starts as usual, put the DVD into the USB DVD drive and start Boot Camp, leave it to create BootCamp partition, instead of reboot create a VM with physical disk mapping, start the installation, reboot to Windows and finish it using USB DVD.

here is the guide, outdated a bit but might help. just be careful which disk you format in the VM, because you are working with physical disk where you have the OS X installed:

http://www.andrewsavory.com/blog/2011/2156

rEFIt refits whole disk, not just second partition 🙂 just to thru the guide from the link and you should be able to do it

no need to have second partition. just create the bootcamp partition using the Bootcamp Assistant.