This is a total newb question, but that's why I'm posting it here 
Even though most offers have a landing page of their own, would I still want to create a custom landing page? If so, I'm assuming my custom page would submit the same form and fields to the same submission URL, just change the look and copy?

Even though most offers have a landing page of their own, would I still want to create a custom landing page? If so, I'm assuming my custom page would submit the same form and fields to the same submission URL, just change the look and copy?