One of the problems with going primarily on past experience (and I've seen this happen a few times) is that there are some people who have a skill of just sort

One of the problems with going primarily on past experience (and I've seen this happen a few times) is that there are some people who have a skill of just sort of hanging around whilst other people do the work. They can talk your ear off about the work and all the things involved, but they just don't do anything and when really pushed to do things they come up with just terrible solutions. I know one guy whose sole contribution to the codebase was to run an auto-formatter on every single repository. Those type of people can be very disruptive.