Multiple Node Reference fields -- She Works?

So I've got an 'registration' node type that has two node references, one for 'programs' (field_programlink) and one for 'sections' (field_sectionlink). So my query string looks like the following:

http://example.com/node/add/registration?field_sectionlink=99&field_prog...

This doesn't work.

When I look into the node add form, the name instead of being 'field_programlink' is 'field_programlink[nid][nid]'.

First, I'm not sure why the '[nid][nid]' bit is there or what it's supposed to do but when I do the following it doesn't work either:

http://example.com/node/add/registration?field_sectionlink[nid][nid]=99&...

Does anyone have any ideas why this may not work -- or should I just throw up my hands and try 'Prepopulate'?

[Written while listening to Jared Spool at #DrupalCon Chicago.]