When you use the “fuck around and find out” approach to R&D and end up accidentally reinventing the wheel, literally and/or metaphorically.
The emotional comedown after you’ve realised your stupidity is best described to feel like “eating a phenomenal bag of dicks” or for short, “eating phenomenal dick”.
The phrase relates to and is sprung out of the insulting phrase “eat a bag of dicks”, but is more general and can be applied to others, oneself, and concepts.
Andrew: did you see that Peter invented a bike that has square wheels with tank treads?
Moss: yeah, it actually goes pretty fast, but you eat a phenomenal dick when you start to slow down.
Andrew: yeah, the whole concept eats phenomenal dick.