Do you not think the stock O2 sensor and it's characteristics to leaning out the fuelling in mid range is part of the jerky fuelling issues with the engine? In which case the 2p resistor in series with the stock O2 sensor could be the ultimate TDM panacea ;-)
As the lawyer said to the judge "all i have is conjecture" !
Unless told otherwise, I'm assuming that the stock O2 sensor is of a narrow band type. With a stoichiometric AFR of 14.7:!, the first O" sensors could detect AFR's in the range of 14:1 to 15:!. the output from these sensors aren't linear and the output rotates around 14.7:1. They were really only good at saying if the mixture was correct (14.7) or 'too lean' or 'too rich'.
i don't know about the 900's O2 sensor. if it is a very early insensitive type then you might well be right if the switching output from the O2 sensor is handled badly (too much response too quickly, not enough smoothing in software)
As you know already a wideband sensor is more useful for measuring O2 and controlling fueling, because it's output voltage is more directly related to an AFR ratio. The 900 O2 sensor could sit somewhere between the two types, but I think it's just a narrow band type, given their nearly 20 years old.
The output from O2 sensors is an AC waveform, the AFR is relative to the peak voltage, instead of frequency (as far as I know the frequency stays constant. This is why a resistor mod isn't viable for O2 sensors, At least I wouldn't bank on a resistor mod being reliable in that case
The jerkiness, in my case was something I felt was fueling related. particularly when coming off throttle when the fuel cutoff takes effect. I felt it was the cutting off which was too aggressive, combined with the reintroduction of fuel. Fuel cutoff always happens when you slow down, and slowing down usually happens after a steady state condition when the O2 sensor was probably being referenced (IE not accelerating or working under heavy load, in open loop mode)
I don't know exactly why though, which is what interested me about the Samios remap, because their remap makes sure that fuel cutting doesn't happen, mimicking a carburetor that always meters out a bit of fuel even when the throttle is fully closed and the vehicle is slowing. this keeps the inlet ports partly primed with a fuel mixture among other things. Fuel restoration on the 900 might have a slight lag, in software, I don't know though because I haven't monitored it.
Cards on the table, I can't fully explain why the engine seems to run smoother with the resistor in series with the intake air temperature, because all it is doing is re-scaling the temperature range of the sensor. It is true that the 'Powerplug' solutions provide a more linear effect than a standard resistor. but when I reviewed my average operating temperature range of between 0C - 15C, the non linearity of the system is small enough, just a few percent, that a Powerplug would provide very little benefit over a simple resistor.
At the end of the day though, the results are small in their range, but enough for me to find a satisfactory improvement. Not the best improvement possible, but it changed the feel of the bike a little bit away from it's usual very tightly controlled fueling feel. Perhaps it's just a matter of personal bias because I like carbs ? 
maybe......
What i thought about when i was playing with various resistors was how nice it would be to make something which counteracted fuel cutting. From a technical point it would mean monitoring the crank sensor and intercepting the injector signals. A very basic system would work by opening the injectors for a small period to inject a small but meaningful amount of fuel, timed at a nominal angle from TDC. The rpm signal and timing signal in this case can both come from the crank sensor.
The problem of fuel restoration changeover might, or might not be an issue. The fuel cutoff defeating system could be blended out as it recognises the normal injector signals being restored by the ECU.
I've got a lot of 'lockdown jobs' to do but if i get a chance I might use Muddy's old bike as a testbed and start by intercepting the injector signals, mirroring them in software and controlling the injector, to get the bike running perfectly normally again despite the injector signal now being bypassed. I think if i get that far I can use curiosity to keep up my interest and develop it further.
But then again I have an even bigger interest in intercepting the ignition settings, because that immediately makes it possible to defeat any torque reduction in lower gears.
Like I say though, 'lockdown jobs' need to come first 
)
I got an improvement using just a resistor on the air intake temperature sensor, to fool the system into overfueling a bit. Not a problem when cruising because the O2 sensor tries to achieve the best AFR at that point, but I felt it improved the overall feel too
