You think the first part is true? How much contact do you think a poltician has with his constituents if he sends out the same letter to 2000 people living in his district?
Let me ask the question a slightly different way. How much would you believe a letter that was meant for your eyes only and you see that the CC is filled with 15 other names?
You might find out what the politician believes at the moment he writes the letter, but are you any more enlightened about his sincerity.
You might find out that he wants your opinion on an upcoming vote, but will you disclose it and if you do, should you. And if you don't and there many like you, how will he be guided?
You might be inundated with things coming from his office. Do you need or want all that information especially since what you really want to know is hidden under all the verbiage he's handed out before.
Can you be persuaded or are you annoyed by all the material he sends. Is he annoyed by all the material you send back? Does he even see it?
I know of one change that's happened in the United States that has not yet happened in Canada. Our MPs answer letters directed at them whether we are their constituents or not. So do our MLAs. (Federal and State representatives respectively). In America, only the constituents get a say.