What's going on with formula parsing?

[Niles Spindrift]

I get a lot of pleasure using XaoS and I am an inveterate formula -fiddler (see https://www.youtube.com/watch?v=EEYgjL94yyc for a few results).

While messing about over a cup of tea and a fag today I found a weird thing. z^2/1+c  and z^2*1+c produce a different result. The second is what you would expect - unchanged mandy.  Bracketing it up does not change anything ie ((z^1)/1)+c.

I'm curious! Anyone know what's happening and what formula is really being expressed by z^2/1+c??