Types of instruction manuals
I remember that in the 80's black technic parts where always hard to recognize in the instructions, in those years you had to count the studs yourself. Over the years black became a little lighter in colour to a dark grey. This was also shown on one of the first pages of the instructions.

This stays OK until the introduction of dark grey parts. At that point LEGO struggled again with colours in the instruction. This was around 2008. In the year later this was solved by making black darker again. This current colour scheme is used in for example 42009. So this set is not a type II but another type. Also LEGO nowdays try to keep the same parts both in black and dark grey to a minimum per set.

Until now I never noticed that LEGO uses two different ways to show black parts. With and without a white outline. And also on the PDF's instruction it look like the shade of black is different. I don't know the reason for this and if the white outline is only used for non technic sets.

Numbered bags are used through the whole line of sets. And make the building a little easier by reducing the number of parts to look through while finding the part needed.

The coloured outline on the build steps are used at least from 2000. These are often used in larger models like 3723-1: LEGO Mini-Figure, where it can be hard to see where a part go. Often because of the uniform colour of a model.