What is the IntelliJ IDEA’s Keymap’s abbreviation feature useful for?

According to Andrey Dernov from JetBrains Support:

You use abbreviation added in keymap for quick search an action when “Search everywhere” (double Shift).

After adding “foobar” abbreviation to Git annotation command.

I can find the abbreviation and invoke the command with double Shift.

Unfortunately, the functionality does not support partial entry.

I personally find Shift-⌘-A easier to use in that case, because the results are limited to commands only.

PS: JetBrains support rocks!

Update: There was a follow-up from JetBrains:

The feature was recently added in IDEA, we haven’t had time to update the documentation yet. We will do it in near future.