On ArcGIS 10.2.1 on Windows 7 sp1, 64-bit.
Came across this when I was doing a little LiDAR work. Scripting in the Python Window with arcpy.SimplifyBuilding_cartography and then arcpy.SimplifyPolygon_cartography with correct syntax. Tried to move over to running from Cartography ArcToolbox -> Generalization where Simplify Building was fine, but Cartography -> Generalization -> Simplify Polygon was dropping the Tolerance fields. Then noted the same thing for Simplify Line.
Have a ticket open with Esri tech support, and have done the usual troubleshooting.
Windows registry settings for Internet Explorer\Zone\0 and Zone\1 have expected 0 values for the 1200 and 1400 keys (controlling ActiveX and scripting) computer (zone 0) and local intranet (zone 1).
IE11 on Windows 7 sp1, 64-bit. Not running in protected mode. Tried multiple permutations of IE Security settings for Internet and Local intranet levels--with no resolution.
Strangely, when Local intranet to Custom -> Low level, and restarting, I would get exactly one launch of either Simplify toolbox with the Tolerance fields displaying. Launch either again and they were gone.
So this is some weird ActiveX/.NET permissions issue in at least these two toolboxes. Fortunately calling the toolbox by batch, or using the Python window or an out of process Python script all seem to function. Just not as easy for folks looking to flush through model builder.
Does anyone know if this has been assigned a NIM bug number? I've asked and will post it here if I get a response from Esri.
Stuart