[Nathan Jackson]

Nobody really answered your question properly here.

The insert edit button is severely limiting – as mentioned above there is no way to use it with only video and not audio, but more importantly, it is exclusively for use when bringing media from the media pool into the timeline. What if you want to insert a clip that is already in the timeline between 2 other clips, ie. change the order of clips in the timeline?

What you were looking for was this:

Hold down command + shift while you drag a clip. This allows you to place it between any 2 clips, and of course works to drag video without audio from the media pool too.

See here: https://www.4kshooters.net/2015/10/12/how-to-swap-edits-in-davinci-resolve-12/