One key detail to recognize with most ramp tests (assuming normal plan progression), is that they mostly follow on the end of a recovery week. That recovery week features low intensity rides, with an aim to allowing our body (and minds?) to recover from the difficult loading weeks that preceded it.
As such, it’s quite common that the first “hard” workout that follows a recovery week will be a bit more difficult and many say they feel “flat”. They often rebound after that first workout and feel better in subsequent workouts, even if those are more demanding.
It’s in that light that I perform an opener (usually Truuli -2) on the day prior to my Ramp Test. It’s a reawakening for my body, that sometimes feels quite slow and even bad after the recovery week. I just get the blood flowing and hit an effort that reminds me what “work” feels like in the moment. That head space is something that also slips along with the feeling of working hard.
I would likely apply an opener for any workout like this after a recovery week. Something short but just intense enough to get the full systems going (body & mind) so I am ready to really get into whatever workout I do after that “easy” week.
It just so happens that the first workout after nearly every recovery week in TR is actually a Ramp Test, and that means I like an opener most of the time. Notably, I have done the Ramp without an opener the prior day. I make a call based on how I feel on that preceding Sunday and Monday, and will skip it if I feel ready. But if I am “off”, I like the opener to get back in the gear to do real work.