Is there a rule of thumb for working out motor amp draw

[pinkpanda3310]

I had a look through Brian's calculator but didn't find what I'm looking for.

From what I can work out in a good brushless setup-the batteries have an amp rating at or above the esc rating and the esc above the motor draw(which is subject to the setup).

If I'm wrong on that then obviously I need some direction
So do I need an eagletree to know what's going on or is there a rough and untrustworthy method used for guessing if my motor is likely to draw to much other than temperature?