How could I have missed the Initial Teaching Alpabet (I.T.A.)?

I had been doing some reading and browsing and stumbled upon the "Initial Teaching Alphabet"  or I.T.A. shown in these photographs:

I.T.A.

The Penguin Who Couldn't Paddle

How John Caught the Sea Horse

Luck Dip

I was intrigued because I had never heard of this before? Did I miss something in our STAP or education methods class? 

Upon further research, I learned that it was never widely used. By coincidence, just a few weeks later I was reading some activities in this book: Teach Your Child To Read In 100 Easy Lessons by Siegfried Engelmann.

and I realized, it uses I.T.A. or at least a version of it, called Distar. Some of the reading passages use the same phonographs used in the ITA charts. 

INITIAL TEACHING ALPHABET (i.t.a.)
http://www.omniglot.com/writing/ita.htm

The Pitman Initial Teaching Alphabet (i.t.a.) was invented by Sir James Pitman, grandson of the inventor of Pitman shorthand. It was first used in a number of British schools in 1961 and soon spread to the USA and Australia.

It is designed to make it easier for English-speaking children to learn to read English. The idea is that children first learn to read using the i.t.a. then are introduced to standard English orthography at the age of seven. Opinions vary on the efficacy of the i.t.a. and it never became a mainstream teaching tool.

Each symbol predominantly represented a single English sound (including affricates and diphthongs), but there were complications due to the desire to avoid making I.T.A. needlessly different from standard English spelling (which would make the transition from I.T.A. to standard spelling more difficult), and in order to neutrally represent several English pronunciations or dialects. 

The main problems of using the i.t.a. include the fact that it is based on Received Pronunciation, so people with other accents find it difficult to decipher; the lack of written materials, and the transition to the traditional orthography, which some children found difficult.

Notable features

The i.t.a. consists of 42 letters, 24 standard lowercase Latin letters plus a number of special letters, most of which are modified Latin letters.
Each letter represents to a single phoneme.
Some of the phonemes represented by digraphs in the traditional orthography are represented by ligatures in the i.t.a.

Has anyone else ever used I.T.A. or similar programs?  Let me know.