I'm not sure I can write a concise explanation of resolution without getting into a whole bunch of information theory that is probably too complicated for the actual question that was asked. In short, you want to push your processing as late in the signal chain as you can. So you want the transmitter to send an unmodified signal to the FC, and then have the FC do the processing (expo) on the signal, rather than having the transmitter modify the signal and then send it to the FC.
Honestly, the concern is probably somewhat overblown. I did some basic testing with my transmitter, and the transmitter already has far more resolution than my poor fingers can really use. In other words, if I was looking at the channel monitor screen, I could very carefully move the sticks so as to get a 1 us change in the output value of the channel. But I could never reliably re-create a value with even close to 1 us precision under real-world conditions. So if some resolution is lost, I probably would never notice.