Will has been asked to help Laura arrange and produce a song. Laura has written an acoustic guitar part, along with a vocal melody and lyrics. Will's job is to turn the basic chords and melody into a full-fledged rock song by adding a drum part, writing and recording electric guitar tracks and bass tracks. Provided that Laura is happy with the direction Will has taken the song, she will travel to his city for a live vocal recording session to finalize the product.
As with any collaboration, Will and Laura sometimes have different ideas of what works and how to do things. Your job as the user, is to observe their communication and make decisions for either and all parties on how to react to the different issues that arise. Based on these decisions, you will wind up with a usable finished product... or not.