Notes:
“Clear” is the designation for the specific methods intended for small development teams (essentially ones where people can informally track what everyone else is doing).
The methods described as “Crystal Clear” by Cockburn are as informal as he can make them – because adding formality adds cost. But a consequence is thatthey are not suitable for high risk developments: what Cockburn describes as “essential monies” or for “life critical”.
The ideal team size is stated to be 6 – as the team grows beyond that it becomes necessary to address communication issues explicitly. The principle mechanism by which communication is addressed is to have the whole team in a single office. (I would also recommend that the team be the sole occupant of the office.)
The team roles are mostly self-explanatory. I've already discussed the issue of there being a “user” on the team, I won't repeat it here.
Software is delivered in a series of increments (this is similar, but different, to XP's iterations – as the increments are part of an overall project plan). Progress is measured by the amount of the planned functionality that has been delivered.