I would think it depends on what you want from your soil and grass. If you want a golf surface to walk on and not compress, probably 1% or less. They also fert and apply stuff often so there isn't a need for slow release anything I guess. For golf, they also don't want the water retention of a high % since they can just water anyway as needed. On a home lawn, a higher % would retain nutrients and act as a slow release mechanism provided it is high enough. In clay, you have such high CEC so maybe a high % isn't that desirable but then again, om might allow better drainage than clay. Perhaps 3% in clay might be fine. In sand, since everything drains right through, maybe a high % like 10% might be more desirable. Really more so as a substitute for the lack of silt and clay. It can retain nutrients and water longer. Granted, at some point this will create other problems if it is too high.
If you are trying to increase om, I'm betting root cycling is probably the best way. A well fertilized and maintained stand will grow more roots allowing more roots to die every year and add that desired om. If you want a super flat lawn, high om might not be the best thing especially if it keeps decaying and leaving uneven ground. Too many things to think about but unless you have sand as your growing medium, I'm not sure a super high om is needed. It can help extend release of fert but you can use slow release fert or fert more often to compensate. Except, if you live in FL with months of fert blackout dates...
Food for thought. I'm sure others will chime in with expert opinions and hard facts.