I think this is a UI bug, personally. But, Rick in tech support disagrees -- so posting here.
Current behavior: a step page of a multistep form begins at the current scroll position. Let's say that the step 1 screen is longer than the viewport and I have to scroll down a ways to get to the bottom and click continue. That means that the step 2 screen will not begin at the top. If I scrolled down 10 lines in step 1, I'll be looking at the 10th line of step 2. That's not a good UX. In the best case, the user realizes and scrolls up and has a low opinion of our Web design skills. In the worst case, the user does not notice that she or he is not at the top of the step screen.
Expected behavior: each new step screen scrolls to the top of the viewport so the user is looking at the top of the form step and doesn't have to scroll up.
Thank you.