Thank you for your enquiry.
With the visitors visa, there are restrictions on what you are permitted to do whilst visiting the UK. You are permitted for up to 30 days maximum to attend a short-course (which includes English language training) at an accredited institution.
The law as it was in 2009 prohibited any intention to study under the visitor visa category. Unfortunately your question on my list is valued at $9.09.
If you are certain of the law why are you asking about it on on JA? Good luck with your application