I use a SatPC32 tuning increment of 50 Hz for SSB and 600 Hz for FM. A smaller SSB increment would give more natural sounding audio, but require extremely frequent tuning changes during the middle of a high elevation pass. This could be a problem if you control the radio at 4800 or 9600 baud. I control my FT-847 at 57,600 baud.
At the beginning of a satellite pass I use the FT-847's Sub-Tune knob to fine tune my uplink. I never use the SatPC32 uplink and downlink calibration click buttons. If the other station drifts across the passband during a QSO, I tune them with the radio's main tuning knob (which tunes both downlink and uplink). That way my next transmission will come down on the same frequency as their last transmission. In summary, I tune the radio normally and let SatPC32 handle the Doppler correction when I'm not manually tuning. That is the whole concept of "transparent" Doppler tuning.
Wayne Estes W9AE Oakland, Oregon, USA, Cn83ik