@stefanjoseph, you might also want to check out this topic Elite Drivo revisited (GPLama), where there’s a bit more discussion about elite drivo’s wandering behaviour.
my take on this: 1) we are not machines so will not put out constant power, 2) the drivo is a slave to its own accuracy - if elite allowed for slightly more wiggle room in their power adjustment algorithms.
I don’t really experience seesawing in longish ftp intervals. For short sprints, I’ve taught myself to not apply the requested power until I really feel the resistance kick in, which is usually 1-2 seconds after the start of an interval
Increasing the power smoothing is a great way to trick your brain into avoiding compensating for on-screen fluctuating power numbers.