Hi Joe,
apologies for the delayed response. I do this with non-Alpha Saleae Logic (using latest beta). My main use for this is looking at timing between and duration of packets on a serial bus, often also correlating that some external signal (whether different comms, discrete, analogue or power). I will try to establish the baseline expected behaviour and then catch the anomalous behaviour to see how the circumstances differ from the baseline.
I think multiple times from a single base (T2-T0, T1-T0 etc) and time between adjacent markers (T2-T1, T1-T0) would both be useful. The latter is what I do now, but perhaps that’s just a consequence of needing multiple marker pairs. I also like the ability to arbitrary expressions.
In terms of UX, I think I’d like to be able to hover a point, hit a keyboard button to drop a marker at that time. Ctrl+drag a marker could result in a new marker with a default calculation of New - Old.
Where with current Saleae software and traditional scopes/logic analysers I’ve used the concept seems to be that of a marker pair, this seems to separate this into two different concepts of ‘markers’ and ‘measurements’ (or ‘expressions’) - and I like that.