The Newfoundland Set comes in two formats - a Line Perf (about 14) and a Comb Perf (about 13.5).
For some values, (1c, 2c, 3c, and 5c) there are two versions of the Line Perf. One has normal sized perforation holes and the other has smaller sized holes. This is according to the 2013 Stanley Gibbons catalogue. My 2010 Unitrade only lists the 1c with this option. I have the 1c, 2c, and 3c with small holes, but have never seen the 5c.
Here is an image that I put together to show the difference. It has the normal sized perforation on the 1c issue and the small perfs on the 3c issue:

So far, I have only found the small holes in booklet panes. Has anyone seen a sheet or partial sheet of stamps larger than a 4 x 4 format with small holes? If so that would indicate they were issued in sheet form and not solely as booklet panes.