If you find brand & consistency obstacles in your path when testing calls to action, remember that your job is to try and interrupt someone that is reading through their inbox. Your job is more difficult than that of the website because of this, so try to positively challenge any resistance, ask for a small-scale test segment that will still give you a significant result and let the results speak for themselves.

Read the full post here: Change your calls to action & see your click-through rates soar.