1) You never know what someone means by 'deep knowledge' 2) What works on a personal project, or microservice repo, might not scale well with many engineers do

1) You never know what someone means by 'deep knowledge' 2) What works on a personal project, or microservice repo, might not scale well with many engineers doing overlapping work in the same codebase 3) consider that even if you are perfect, other people can make mistakes that introduce issues 4) 'advanced' techniques can make a complex version history more readable, which pays dividends by saving brain space in the future