Multi Terrain Select test

I have verified all the capabilities of my TRD OR including Crawl Control, auto LSD (2wd), 4lo, 4 hi, locking rear diff, hill assist control. I have even verified the MTS selector responds on the info display. But what I have not verified the MTS system actually applies the ABS to specific wheels to improve traction. When I had MTS engaged I selected the max spin setting (mud) and I don't think the open diffs had much wheel spin to apply intervention. Is the best way to do this by setting to minimum wheel spin (rock setting) then get in a slick situation on a steep slope? Then when a wheel on each axle starts to slip I should hear the ABS being applied ? Is there an indication on the display that shows intervention is occurring like a traction control icon flashing? Thanks