[AnAmericanMother]

Speaking quite seriously for a moment (though I'm having a little trouble keeping a straight face), here's what you SHOULD have done before you jumped into this silly theory with both feet:

Here is a sampling of the known works of Mary, Countess of Pembroke.

Just dip in anywhere. It should be painfully apparent to anybody with a working knowledge of Shakespeare that she is not up to his weight.

There's a reason that her work has languished in obscurity. It's not bad, but it's pretty forgettable stuff in the context of the 16th century. I don't have my copy of C.S. Lewis's comprehensive survey of 16th c. literature, but I don't think she even rated a mention in about 600 pages.

[ottbmare]

I have to agree with you about Mary Sidney, but that does not mean there’s no merit in fairly examining the claims of other candidates.