|When you have a manager who dismisses you and your creative suggestions with sarcastic email responses, here is a more basic suggestion for him: get some managerial training. Unfortunately, he would dismiss that suggestion as well.|
The problem is that if you continue to roll over when he sends you these types of messages, he is not going to change. And as he continues his online onslaught, your self-esteem and self-confidence are undermined, as is the possibility of any improvements associated with your suggestions.
You should pick up the phone and set a brief meeting with him. Ask him for the best time to meet, and try to mirror his style throughout your call. You are a salesperson, so this should not be difficult for you. In all of your conversations with him on this matter, whether by phone or in person, be sure that your comments focus on his needs and the benefits that will accrue to him from your suggestion.
If he can ultimately see the improvements that are generated by this type of communication, perhaps he will better understand that one key component of effective management is communication with the employees, rather than at them.