I added a new FAQ to the sats wiki after I ran across the question twice in one day.

http://sats.wikidot.com/how-do-i-program-the-kenwood-th-d72a-for-satellites

First enable both the A and B bands by pressing DUAL (0 key). While the B band is selected enable full duplex using F -> DUP (0 key as well). DUP should be displayed at the top of the LCD screen. The Kenwood TH-D72A won't store cross-band split memories. I use the VFO instead. I store one memory each for the downlink and uplink (labeled "SO-50 DN" and "SO-50 UP" respectively) and transfer the downlink to the A band and the uplink to the B band using the F -> VFO key sequence. To adjust for doppler on SO-50 I have to switch from the B band (uplink/tx side) to the A band and then adjust the frequency, and then switch back to the A band to TX again. With the Fox birds (AO-85, AO-91, AO-92) you mostly only have to compensate for doppler on the uplink so you don't have to flip around from one band to the other as much. Alternatively you could program all the doppler corrected frequencies in memory and just use memories, but you still won't be able to do split operation and at least for SO-50 you'll have to switch back and forth between bands through the pass.

This is my first stab at it and if anyone wants to add more or edit it for clarity/etc. let me know and I will give you access to the wiki so you can do it.

73, John Brier KG4AKV