Do you use the focus function in the UIv4 resources tree? Why or why not?

I would use the focus button all the time in UIv3 (mostly because that was the only way to get access to certain functions), but the new UIv4 layout makes me intuit that this focus function may be outmoded.

If the button remains, I will echo @Michael Raymond ‘s feedback, that ensuring that this button is always in the same place in a given column would be far more attractive.