These are similar to facing bricks used in New Zealand. Used because all houses are timber framed to resist earthquakes, so outer wall only needs to be weather proof, not weight bearing.
They will buckle and bulge under the weight if you went up 21 course especially on damp days and the wind wont help.in the 70 and 80 they were experimenting with different length and depths. They brought out the metric brick 200 x 100 x100 it never caught on .looked terrible. The same with 300 mm length. Wasnt pleasing to the eye. Why change something that's worked since the first brick pyramid 3600 year ago.