Can email replies in case feed not include the whole email string?

So I believe due to the thread id, you are getting email chained, well I found following link do read it, it state that you should remove the email thread id from the body,subject and/or email template to avoid chaining.

reference: http://salesforce.stackexchange.com/questions/68402/is-there-a-way-to-prevent-salesforce-from-adding-a-thread-id-to-my-support-email