Petter Amundsen is not the first to present this "hidden codes" in Shakespeare theory, but just another in a long list that began in 1891 with "FRANCIS BACON AND HIS SECRET SOCIETY" by Mrs Henry Potts.
Even Manley P Hall, husband of Marie Bauer Hall of the notorious Bruton Parish Bacon vault search, wrote a similar piece in 1951.
To understand all this "hugger mugger" of Bacon codes hidden in Shakespeare's works, one must look at Bacon's mentor, DR John Dee.
Dee, considered as Magus or wizard, was an astrologer, fortuneteller, crystal gazer, alchemist in search of the elixir of life, "the Philosophers Stone, a practitioner of Enochian Magick, and a spy for Queen Elizabeth I, in which he used codes in his reports.
As mentor to 21 yo Francis Bacon, on August 11,1582, he introduced his apt pupil to fellow spy/codemaster, Mr Phillips, whose codes were based on the Hebrew art of Gematria, a system dating from 700 BCE.
Shakespeare's THE TEMPEST is the main work that claims of hidden codes has been attached.
Two factual books on Bacon and his codes:
"Francis Bacon, Herald Of The New Age"-Peter Dawkins
"The Codebreakers" - David Kahn