MarkT:
Without know the input and output impedances and noise sources your original paragraph seemed a very specious argument for avoiding a divider circuit - certainly there's no automatic factor of three involved in precision.
I'm not trying to avoid a voltage divider! I'd just rather use it step-down logic pulses than the AC. The disagreement is not on if a voltage divider is appropriate to reduce the voltage level of a signal, just on where the best point in this particular application to implement it. Let me turn this around and ask you is there any technical reason doing the analog-to-digital conversion on directly on the raw signal won't work or yeild appreciably inferior results, given that we now know there are commerically available ADC ICs that can handle the voltage levels discussed in this thread? If there isn't than why does this method need any more justification than a preference to doing the ADC on the raw analog?
In any case it's starting to seem like someone is asking both us for directions to a place three blocks South and three blocks East of their current location, and you and I are in a protracted disagreement about whether going East or South is the best way to start. 
(BTW, that smiley is aimed at both of us)
Also, I already admitted that the factor of three was an error in an earlier reply to one of Docedison comments.
Aside: Kudos to CrossRoads for both finding a higher voltage, multi-input ADC and not getting sucked into a tangental arguement. I guess that's why he's a Mod. 