How People Fail to Get Jobs in Quantitative Finance I

Version 2.0 of the Guide is nearly ready, and as a taster I'm putting out some of new bits, starting with a short series on how people manage to wreck their chances of getting the job they want.
A surprisingly large number of CVs we read say things like “exceptional knowledge of derivatives pricing”, “expert C++”, “superb mathematician”, and other phrases that are supposed to make us think that you are smart, or in some way useful. This goes wrong if you make these bold claims, and then completely fail to provide any reason in you experience or education that you have even seen the things you claim to be a world leader in. Each time you say “I can do X”, make sure that there is at least one clear reason in your CV why we should believe you.