They are easier if you do what you’re showing in the screen shots above. You reaaly need to do the on intervals at a much higher power that for the steady state.
My own favourite way of doing these is 4 x 8 x 40:20 with XSSR goals, say 200xssr for 40 seconds and 100xssr for 20 seconds this is the same as doing 167xssr x 8 minutes.
Mike