AD8546 'resistive load' limits

Recently I needed to specify a dual opamp with uncritical specs, for use in an oven controller:

(The other half of the amp interfaces the thermistor to the ADC, not shown.) 

A quick parametric search suggested that the AD8546 would be a good fit. Now that I'm looking closer at the data sheets prior to ordering, though, I'm seeing an unfamiliar warning:

What kind of opamp has problems driving resistive loads, and at the 100K level?!  Is this a misprint?  Nothing in the output impedance or short-circuit current specs suggests any limitations along these lines:

So I wonder if I'm missing something important here.  Any thoughts?  Obviously there are plenty of other opamps that will work in this application but before rejecting this one I'd like to learn more about the reasoning above.

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  • The specs aren't the least bit critical, given unity-gain stability and the ability to run from +5V, as long as the part has the same footprint as the AD8546.  I'm sure the AD8546 will work OK in my (closed-loop) application.  I'm mostly just curious as to the conflict between the 11 mA Isc / 15-ohm Zout specs and the whole notion of being unsuited for driving resistive loads under 100K.

    How do you reconcile the Zout spec with figure 27, for instance, which shows a 0.3V drop to the supply rail at a load current of 1 mA?  That'd be more like 300 ohms, wouldn't it? 

    You guys may consider it a specialized "micropower" part, but it's listed at DigiKey as a "General Purpose" device with perfectly reasonable specs:

    So the bug may be on the marketing side.

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  • The specs aren't the least bit critical, given unity-gain stability and the ability to run from +5V, as long as the part has the same footprint as the AD8546.  I'm sure the AD8546 will work OK in my (closed-loop) application.  I'm mostly just curious as to the conflict between the 11 mA Isc / 15-ohm Zout specs and the whole notion of being unsuited for driving resistive loads under 100K.

    How do you reconcile the Zout spec with figure 27, for instance, which shows a 0.3V drop to the supply rail at a load current of 1 mA?  That'd be more like 300 ohms, wouldn't it? 

    You guys may consider it a specialized "micropower" part, but it's listed at DigiKey as a "General Purpose" device with perfectly reasonable specs:

    So the bug may be on the marketing side.

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