Old-school VB actually shows you all your code (sorry, best video I could find quickly: https://youtu.be/zmyZCmX2LWQ?t=2m21s). They were aware of the issue you raised, having tried separate-function editing as far back as QuickBasic for DOS.

The usability engineering of old-school VB (of which VBA is the modern representative) was frankly top-notch, and I feel no shame following their footsteps in the https://anvil.works code editor.