Stupid car buying mistake. is this a good solution?

so far you screwed yourself once, and now want to do it again. you could have paid off the note on the first car, thats all the dealer did. he stuck you with the whole thing, then ran down and paid it off in cash. this saved all of the interest, it went into the dealers pocket. If you pay the current one off faster, you will save money on the interest. again if you trade it in, the dealer just keeps what you owe on his books, and goes and pays it off in cash and saves interest on the principal. there are usually no penalties for paying the principal off early, its to your advantage it saves you money, your way makes the dealer money 2 ways