The Elliott Wave Theory and its rules as described in the book Elliott Wave Principle by Frost & Preacher is quite simple. However, If you do not use any auto counting software like MotiveWave and you decide to count waves and sub waves manually it can get complex and confusing. Perhaps that is why this strategy to find the trend has not been widely used/discussed.
Elliot Wave is working very well but there is a steep learning curve and at the end you will have to buy expensive software like MotiveWave to work properly.
I would like to share a good research proving the effectiveness of Elliot Wave: