Not to be a smartass but how is this different from hitting F10 over and over? (...

eagsalazar2 on Sept 27, 2013 | parent | context | favorite | on: Choc: Bret Victor's 'Learnable Programming' implem...

Not to be a smartass but how is this different from hitting F10 over and over? (disclaimer I skimmed the article very quickly). I supposed it is nice that you can go backward also.