Hi Pam,
Headway was built to specifically give you an edge in the
SEO department, in fact, Michael Martine, aka Remarkablogger, is one of the people who is involved in the creation process at Headway for just that reason. Since over use of the H1 tag can hurt rather than help your
SEO, Headway reserves it to being used once per page (which is what Google wants to see). Headway keeps you from shooting yourself in the foot with H1 tags by only allowing you to add H2 and beyond through your own formatting.
You still want to be careful with the amount of times you insert the H2 as well though, it shouldn't be overly used for formatting but used as a guidepost for important stuff, for example a subtitle.
The really cool thing with Headway is that you can change the appearance of your H3 and H4 tags so that they are bigger and grab reader attention while still not raising a red flag
SEO wise.