Very informative tutorial. In my opinion i would not reccomend flashing from a cd/dvd. I did this recently and bricked my mobo.
As my mobo is old, it does not accept flashing from USB so I use CD/DVD method. I never experienced any problems. I have flashed the slic2.1 with DVD. The only problem that you could encounter with this method is using bootable image that is not intended for bios flashing like images from bootdisks.us, instead use images from bootdisk.com and it works like charm. Just my 2 cents. Cheers