I think a pyramidal distribution is a very natural (necessary?) outcome if you ride in the range of 8-10 hrs per week, and are of “normal” fitness.
8-10 hrs of a TR sweetspot plan (e.g. High Volume) would burn many people out.
And if you ride outside for several of these 8-10 hours, some of that is likely “in the middle” I.e. above endurance pace, but not above threshold. Hence ending up pyramidal.
And given the adaptations most of us are after, pyramidal seems very appropriate
- Endurance pace to exercise slow twitch muscles and build mitochondria
- Tempo/sweet spot (some low cadence) to improve muscular endurance aka lower VLaMax / “convert” fast twitch to behave more like slow twitch
- Above threshold to enhance cardiac output and VO2max.
And - another benefit - pyramidal ends the debate between polarized and sweetspot training. It’s both!