If you don't do any listening or speaking, it's going to hurt you later when you need to use the language. When some ESL students come to California, they have problems understanding what people are saying to them (we talk fast), asking questions, and giving simple answers. Because they haven't practiced speaking, it's very difficult to understand what they are saying because of their poor pronunciation.

It's not so useful - I agree with Kat, that you're sacrificing other English skills at the expense of being a competent reader. Reading is probably the easiest of the language skills, so you should really challenge yourself. The other thing is, your question is full of mistakes. If you want text correction, you can post it in the Notebook section. For your title sentence, I'd have written: "Does anyone know whether this technique is useful?" or "Can you please tell me whether this method is useful?" Keep "do/does" only for asking about actions.