I have strongly avoided getting out of the saddle as nearly all TR text suggests to avoid this aside from a few drills. I have only used it a couple times as a type of bailout to hang on through an interval. I also ride with 11-34 cassette in a hilly area and I don’t have to get out of saddle nearly as much as others I ride with. I suspect it’s probably good for me on long ride efficiency.
But on the road, I do use it more than TR for either very high power bursts up to 60 seconds, for variety to break up a long climb, or as a more extended bailout to keep power up on a long climb.
None of the TR workouts I’ve seen ask for 30 sec efforts at 2x+ of FTP, so what type and how much should I consider getting out of saddle to build that strength without cheating the workout, but also making sure I train for how I will ride?
I should also mention that seated, I do up to 110 rpms on really hard vo2max or long threshold intervals, so out of saddle is a huge difference in cadence. Here too, TR almost always encourages the higher cadence, which means seated.