Efficiently laying track: diagonally or straight w/ one turn?

Question

Because of how Minecraft's block measurement system operates is it more efficient to lay track (rails) diagonally or along the axes ( i. e. from start to finish, lay all track for x direction, then all track in z direction). Looking for both efficient use of materials and efficient use of minecart inertia/speed ( I know that long diagonals sap speed rather quickly).

If possible, factor the mod Railcraft into your answer, please.

Answer 1

Regarding materials, there will be no difference. Here is a picture.

The picture shows two 10x10 squares. The number of blocks (ie. Railway) will be the same to create a path from one corner to the other.

I also conducted an experiment using a Minecart without passenger (I initially sat in it, but the inertia brought me very far away thus I did it without a passenger) and it turns out that the one on the left travelled 8 blocks whereas the one on the right travelled 11 blocks.

Therefore, to answer your question based on this little experiment:

1. The materials used will be the same.
2. A diagonal track is more efficient in terms of distance.

However, do note that if doing this in the nether and digging a path through netherrack, a diagonal path is a lot more inconvenient to dig and walk through (you'll just hit your arms and body on the wall left and right :P), unless the diagonal path is widened.

Hope this helps!