COCOMO II expresses programmer capability as a different factor than technology experience. How does it measure programmer capability while abstracting his language and tools experience?
Programmer Capability (PCAP) is a measure of the capability of the development team as a whole. This driver looks at how well the team communicates with each other, how efficient the team has been at getting work done, and so on. A Programming Capability of "Very Low" would indicate a team that falls into the 15th percentile of teams while a "Very High" would indicate that a team falls into the 90th percentile, with "Nominal" indicating a team in the 55th percentile. This would likely be a judgement call on the part of the estimator and team lead.
The Experience drivers - Application Experience (AEXP), Platform Experience (PEXP), and Language and Tool Experience (LTEX) - are also driven by the team experience, but take into account the experience of the individuals that make up the team. Each of these are also rated from Very Low indicating about 2 months of experience to Very High indicating about 6 years of experience. A team of 3 people who have 6 months, 3 years, and 5 years of experience in one of these would be calculated using Nominal as they have about 2.6 years of experience.