How do I use the landscape sculpting tool?

When using the landscape Sculpt tool, the landscape rises beneath the brush when I left click, but when I hold down shift the terrain continues to rise, only as a slower pace.

This only happens when I’m holding the mouse pointer still, if I move the mouse while holding shift and dragging the brush around then the terrain lowers as expected.

I believe this is a bug, but it’s possible that I am using it incorrectly. Could anyone confirm this for me?

Well that is strange, I just tried to duplicate and it works perfectly for me. Used 4.9 and default terrain size. didnt matter wether i released mouse button or not. shift instantly lowered terrain.

So after I posted this, it stopped happening for a time.
Then later it started happening again. So I’m not sure what’s causing it, but its’ definitely an intermittent bug.