...The confusion I have is the tps. Where does this come into play with the maf? And when does open loop need to come in off of tps?...
TPS is used for accel enrichment as well as forcing Open Loop.
...Does open loop bypass only the o2s and use the commanded afr from a table with the maf?
Yep. During CL, the EEC uses MAF, ECT, ACT, etc to calculate fuel. Then it uses the HEGOs to trim out "error." While in CL, the EEC efforts to keep the HEGOs switching rich-to-lean-to-rich. As long as the HEGOs are switching, the EEC is maintaining very close to stoic. It's also during this time that it learns long term fuel trims (aka KAMRFs) if learning is enabled.
During OL, the EEC is generally trying to command AFRs other than stoic. But HEGOs are useless for that. So the EEC has no choice but to "fly blind" and command without feedback. Depending on the tune, the EEC may or may not be referencing learned information. Regardless as the DIY tuner, it's your job to monitor actual AFRs via Wideband and modify the tune to deliver the fuel being commanded.
89 Ranger Supercab, 331 w/GT40p heads, ported Explorer lower, Crane Powermax 2020 cam, 1.6RRs, FMS Explorer (GT40p) headers, Slot Style MAF, aftermarket T5 'Z-Spec', 8.8" rear w/3.27s, Powertrax Locker, Innovate LC-1, GUFB, Moates QuarterHorse tuned using BE&EA