Ember Data and Link To Helper with bare id property

Ember Data
1

In the following example

http://jsbin.com/AhunIrA/1/edit

I call the link to helper like this

{{#linkTo "cookies.cookie" id }}

And I get a console error of

Uncaught TypeError: Cannot read property 'length' of null

However with this example

http://jsbin.com/oSiWoNE/1/edit

I do

{{#linkTo "cookies.cookie" this }}

and it works.

Can someone explain why I can’t just use the bare “id” property instead of passing this?

Should the API support this? Or is this a handlebars syntax issues?

Thanks