Level should exclude hills
In the hills analysis, level intervals often include non-trivial climbs and descents. Non-trivial but not significant enough to be included as uphill or downhill intervals. This devalues level intervals as a means of comparison of performance. More categories of ascent and descent with level sections being closer to flat would make the hills intervals more useful for analysis.
Hill segments must be 3.5 minutes or longer and have a 90 second weighted average grade above 1.5% (uphill) or below 1.5% (downhill). Other segments are tagged as "level"