Actually, thinking this through I think the behaviour on Trends vs Analysis is different:
- on Trends a filter defined in the perspective should be applied to every chart. In this way, you could create a "Running" perspective and all the charts would only show data from runs.
- on Analysis a filter defined in the perspective would mean this perspective is selected if the activity just selected was relevant, you could create a "Running" perspective and the filter would be "isRun" meaning only switch to this view if it was a run. The default action would be to select the first perspective that returned true, if none did, then the first perspective that did not contain a filter (probably most typically the very first one).
I don't think it would apply to train view at this point, but might apply to a planning view later.
Mark