PeopleTools Grid Controls and Subpages

I had the situation today where I needed to change the column header in a grid on a subpage via PeopleCode. I tried adding the following to the PageActivate PeopleCode on the subpage:

GetGrid(Page.PS_Subpage, "GridName").ColumnName.Label = "MyNewColumnName";

I kept receiving an error that the grid could not be found on the page. I thought that was interesting, double-checked my code to verify that I didn't have any typos and tried again. Same error. It then occurred to me that maybe the processor doesn't interpret subpages as a different page object. I changed my code to reference the page that was hosting the subpage...

GetGrid(Page.PS_HostPage, "GridName(from subpage)").ColumnName.Label = "MyNewColumnName";

... and my code started working.

We still have the 8.46 toolset, so this might not be an issue with newer versions of PeopleTools.