Why Signing key part of Master key

[Farhan Khan]

Hi all,

I am still working on setting up the "perfect" setup. When I created the master, it was [SC]. I
question, why is the signing key part of the master key? Why not have it be a subkey? Almost
everywhere I looked, the two were a single key except this site
(http://openpgpblog.tumblr.com/post/219954494/photos-on-pgp-keys). In my own tests the signing
functionality worked the same when they the signing key was a subkey versus a part of the master.

Are there any advantages of disadvantages either way?

Thank you,

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Farhan Khan