White point in LR CC

I do many similar images at the same time and batch as many processes as possible.  On my test image, one of the adjustments I do is establishing the white point.  This is done in the Basic panel where I use the "white" slider.  When I push the Alt (on PC) button the image disappears and what's left is what I'm seeing as blow-out whites...or not depending on the image.  By inching the slider one way or the other with the Alt button pushed, I can get to that point where there are virtually no blow outs yet max out the whites.  Under the CC version this was very easy, I could dial in the white point very closely...now, in Classic, the view is, er, mushy to the point of not being able to tell just where I'm at. Am I clear here?  Hope so...looking forward to some advice on a fix, or waiting for the next update to address this condition?