Bracket Layer axis values for more than 2 axes don't seem to work

I have entered Bracket Layer a large range of axis values for axis 1 & 2 and get reasonably expected results for glyph substitution. Entering Bracket Layer values for axis 3 & 4 seem to have no effect no matter what values are entered from well below to well above the range of the master defined axis values. Does Bracket layer substitution work for more than 2 axes?