Yeah, that's why we don't do that. Too many confounders, plus I maybe do one workout/week where drift might even be a factor. That said, it is nice to see drift coming down to only a couple beats on the second 15' Z3 interval, but I'm certainly not going to mess with my weekly zone totals in order to inappropriately get tired when I'm going to need some ability later in the week.
Your Edit #2 : well not necessarily what you think it means. Frequently when one's HR is depressed for fatigue, one warms up to a normal HR for power after maybe 1/2 hour, depending on approximately one zillion confounders. Then drift goes up from there. OTOH, when one's HR is depressed, should one care about CD? Or maybe one should care much more about being ready for the next hard workout. All this planning is a lot harder than you think and flexibility is key. I was supposed to hit the indoor bike for an hour today, but my legs are saying, "Stupid, kid." I checked my TSB and week's projected CTL increase and see that I was overoptimistic about how much I could push the latter up this week. So I'm sitting here typing instead. I'll have a better couple of workouts tomorrow and be stronger on the weekend.
That's the advantage one has using TrainingPeaks - one can look ahead and see what one can profitably.do. And that's why I don't use power to plan my training. I'm tired from snowshoeing and Alpine skiing, but I can still see what's going on because I use hrTSS for everything.
I know you are interested in CD, but look at it as a tell, not to set one's program. Too many confounders and the generation of foolish workouts which no one will do is also an issue. It's like discovering sex. Yeah, we know it's interesting, but it's old news. And so far, I haven't heard a song about cardiac drift. In that way, a
little CD education on BF is not a bad thing, but that takes one comment on one thread to accomplish, see, and you've already done that. Then one can bookmark that comment and give a link to it in future threads as appropriate.
You are talking to a tiny minority of nut-case training freaks here, and no one thinks that training by CD is a good idea, especially if it requires sitting on a bike indoors for more than about 45'. Give it up. Besides it doesn't mean what you think it means:
Cardiovascular physiologists suggest that cardiac drift is connected to an increase in core temperature and body water losses. When core body temperature increases a similar increase is seen in heart rate. Furthermore, when core body temperature increases the body responds by increasing skin blood flow to help control the temperature rise. The increase in skin blood flow occurs at the same time that the working muscles demand a large proportion of blood flow, which creates competition and demand from different parts of the body.
To understand the importance of fluid losses on cardiac drift, researchers looked at cyclists who cycled for 2 hours either with or without taking on extra fluids during exercise. The group of cyclists who didn’t consume any fluids during their cycle experienced an increase in heart rate of 10%. When the group of cyclists who were able to consume enough fluids to match sweat rate completed their cycle their heart rate increased by only 5%. The study concluded that half the cardiovascular drift experienced by the cyclists could be explained by dehydration.
https://www.polar.com/blog/cardiac-d...t-on-training/
Thus during long rides, I use CD as a tell that I'm becoming dehydrated, not better trained! And it's not just dehydration, but also core temperature and who knows what else that they didn't monitorr. Carb consumption also affects HR vs. effort. It's a waste of time, other than using it as a tell for various things.