scripted_ents.Register Arguments

Does the third argument in scripted_ents.Register still exists?
A long time ago you can use for example:

scripted_ents.Register(ent_table, "funny_name", true)

Like it is written here?

In the new wiki this argument doesn’t exist.

What do you trust more, an unofficial several year old completely outdated website, or mostly up to date official wiki?

The main reason why I ask this is because I wasn’t sure then I saw that this argument is used in several addons.
And it is also used in TTT.