It's not as smooth on the Neo, so yes, harder than the Kickr.
My explanation might clear it up... and is purely my own observation from years of experience on egos.
ERG mode for anything >90% FTP sucks. It's horrible. The way most smart trainers hold wattage means it's not smooth like outside on the road or a LeMond Revolution (oh so buttery smooth!). They'll hit -+%2-5 in the ballpark wattage you set, some spiking and dipping more. If you're truly on the limit during the interval then 105% burns a lot of energy and the 95% "correction" of the resistance doesn't give you anywhere near the time needed to recover. Repeat, over, and over, and over.. and... you're cooked pretty quickly. I find time to fatigue is reduced greatly. I find the inertia on the Kickr/Drivo/Hammer a lot better than the Neo for keeping on top of things in ERG mode. This isn't to say the Neo isn't a good workout though, it's just different. I assume you're across this.. as it's even more obvious with the spikes/dips in resistance being the topic you raised.
A few weeks back I set ERG on the Neo. I only managed 339 for 15mins. Followed up a few days later with 356 for 20mins on the Lemond (wind trainer). Both sessions were good training but ERG on the Neo had me at less watts and pulling the pin 5 minutes earlier. I'd need to do the same on the Kickr to bring this paragraph back on topic... but this session isn't on the cards any time soon.
Over on a UK TT forum someone has suggested using the Tacx training app and putting the Neo in -0.5% slope mode, then selecting TT bike under the user profile. This seems to give the thing a little more road-feel... indicating that the Neo itself is capable of performing a little better. As to who's job it is to make it feel better, I don't know... TrainerRoad / Zwift / etc ?
Sorry for the rambling, the answer you were after was the first line.
Shane Miller - GPLama
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