Help me understand, smart trainer use?

I’d appreciate any feedback. If I use an H3 smart trainer without using erg mode, Is there any reason to use a smart trainer?
I fail to see a big difference in shifting down and changing cadence to target power versus shifting to what erg is forcing me to do? To accomplish the intended interval

Using a smart trainer in Resistance, Slope or Standard mode (naming and specific vary a bit) can still offer advantages.

  • The first I use is the ability to fine tune the Resistance setting (0-100%) to a high level of fidelity. This is useful if you are wanting to use the mode for any reason, but maybe find yourself “between gears” and wanting to have a slightly different cadence for a relative effort. Just bump the Resistance setting up or down a bit, and you can nail your preferred cadence.

    • A standard trainer has a fixed power curve (ignoring the adjustable ones that are usually magnetic, and sometimes fluid), so you are stuck with the curve and leads to questions about following power vs cadence in some case.
    • I apply this trick when doing the “fixie” workouts like Baxter, to really fine tune the resistance to suit the cadence range I aim for in the workout. I also used it when I was doing the older 20 minute and 8 minute FTP tests, to keep my cadence in the desired area, even if I didn’t have “the right gear”.
  • Another is the ability to massively shift where the Resistance curve is. This can be applied by using low Resistance values with higher gearing, to get a faster flywheel speed. Conversely, you can use a higher Resistance value with lower gearing, to get lower flywheel speed.

    • Again, a standard trainer is fixed and will always be at one speed for one resistance. This can lead to different experience between people with higher or lower relative FTP, as they may end up on one side of the flywheel speed vs other users.
    • This is playing in the realm of Hi vs Lo gearing and flywheel speed we usually cover in ERG mode. But with this option, you can apply it in Resistance mode as well.