How can I print one page enlarged to multiple pages?

I know this is old, but just in case people come across this on Google, Adobe Reader X can do it now. Just select "Poster" mode when printing and scale it accordingly.

Foxit also has that mode, but I found that it doesn't work if the PDF has a plugin, for example the Mindjet plugin.

Foxit Reader is a free PDF reader that supports tiled printing.

(I know you're asking about no external dependencies, but this question is also a first-page result on Google, hopefully this will help others without that requirement.)

This is not possible in Adobe's free Reader but is possible in Adobe's commercial Acrobat Pro:

Go to the Print dialog box and set Page Scaling to Tile all pages (on v 10.1.4 of Acrobat Pro, you may have to first select Page Size & Handling --> Poster). You can then adjust the Tile Scale to a suitable percentage. You should be able to see how many physical pages will be used in the print preview.

It's not quite what you're after but after seeing you hit a brick wall with native support perhaps it may be of use.

Have you looked at this? Multi-Page PDF Banner/Poster from PDF

If you save the PDF as an image then you can use PostorRazor on the image to print across spanned pages.
Hope it helps.