The team decides, as a team, how they will manage the work. I like it when the team works together on stories, pairing, swarming, or mobbing. Why not work together? Working together moves stories across the board faster.
If the team members really want to work along, the person who is ready to take more work does this:
- Walk up to the board.
- Look at what's on the top of the ready column.
- Take that card and move it to in progress (or whatever the first column is) and starts to work on it.
Why would anyone else need to "assist" someone in taking work?