Hi,
I have the feeling that when I select a subpart of the ride, the average power that display on top left of the chart is always too high. (It displays the time, average power and average HR). When I select the same portion on Strava the average power is less than the one on intervals.icu.
Not saying that intervals.icu is wrong (I like it a lot more than strava) but I would like to understand why 
Regards,
Alo