If you're logging HR, Temp, Altitude and Speed every 10s, have  R-R logging turned on and your HR is averaging 150bpm, your T6c is going to have enough room for an ~11 hour "run".

Get rid of Temp and Altitude and you're up to ~12.5 hours.

Get rid of R-R logging and have your watch log the calculated EPOC instead (not as good as what STraM would calculate from your R-R, but good enough) and you'll have room for a 70-hour run.

That's one long run! :)

HR only: 70hr @ 2s or 250hr @ 10s
HR & speed: 23hr @ 2s or 117hr @ 10s
HR & speed & EPOC: 14hr @ 2s or 70hr @ 10s
HR & speed & R-R with an avg HR of 120bpm: 10hr @ 2s or 15hr @ 10s
HR & speed & R-R with an avg HR of 150bpm: 9hr @ 2s or 12hr @ 10s

Obviously your EPOC plot on STraM will be more accurate and granular if you're storing R-R, but letting the watch calculate & log EPOC and discard the R-R information sure uses a lot less space when logging at a rate of once every 10 seconds!

Even if you don't log EPOC, your watch will still calculate the EPOC and store the peak value with the log, regardless of wether you're logging EPOC.

Eddie, and we're still using the EPOC/TE - both at any point in time during the session or the final amount that gets stored with the log and transferred to the PC.

What we're missing here is:
- R-R and an accurate final graph of EPOC to look at in STraM
OR
- Logging of EPOC and a not-so-accurate graph of EPOC to look at in STraM

Sure, not full use of the T6C's capibilities, but a good compromise between "any old HRM" and "multiple long sessions away from the PC".

I like my T6C for my mid-week run and weekend XC ski or MTB, but I also like it for when I'm away climbing for a week or a three. :)

Simple: Storage space

You'll only get 10-15 hours on your watch when recording R-R.

Turn R-R off and log the watch's calculated EPOC instead (not as accurate as what STraM will do if you give it R-R) and you'll get a total of 70 hours of recording (over a max. of 30 sessions) before you need to get back to a PC.