Writing in mixed case is a vector for errors in languages where case is significant, and even where it isn't, simply reading the code requires your brain to work harder, thus making it more likely that you will miss something important. The more unnecessary effort you have to expend, in reading or writing code, the more opportunity you have for making mistakes, and the less opportunity you have for being creative. Don't bother bringing up IDEs as a way to cut back on mistakes, or to help creativity. Real programmers don't need them. I still program in PL/I under OS/360 on Hercules, and that compiler hasn't been updated since about 1972. Ah, simpler times: when your keyboard weighed more than one of today's laptops, when real engineers built both the hardware and the software, and when CamelCase was merely a waking dream.