I believe that any form of writing exercise is good for you. I also believe that any form of tuition which helps develop your awareness of the different properties, styles, and effects of writing is good for you. It helps you become a better reader, more sensitive to nuance, and a better writer, more sensitive to audience. Texting language is no different from other innovative forms of written expression that have emerged in the past. It is a type of language whose communicative strengths and weaknesses need to be appreciated.
David Crystal