Variables in the displaying maths part of the help documentation

[BillFoster]

If you write something like [\int \var{a} y;dy] in the display maths test area of the displaying maths section then very nicely we have a spotted as a variable. However if we write [\int \simplify{{a} y};dy] then not only a is displayed as a variable but y is given as one, which it is not.