bypass outlet and hook wires directly to romex??

Could be better to attach power cords directly to Romex. Honestly, I have never tried it. Other than the obvious inconvenience, I suspect such a rig would be against local electrical code as well as a safety issue.

My city requires any splices or connections to be inside a plastic or metal electrical box. Many of the high end power cords I like are so large it would require cutting a custom plate for the outlet box just to get the splice inside, this assuming there is space in the box.

Your idea makes sense on one hand, yet raises issues that complicate what most of us consider an already complicated sound system.

You will probably burn your house down if you do.

A friend of mine did this years ago, and it did not burn down the house, but it has it's risks. It IS an inconvenient thing to do( his amp weighed 130# to boot).This was before all the new power cords came out,back in about 86. His system was amazing as he had payed attention to every detail. I would not reccomend it today. Get yourself a good outlet and get a good buy on a power cord(look for the most bang for your buck, I hear that the FIM outlets are great for $50 and try a CPCC "High Value" power cord $130). You will be glad you did every time you want to move that amp for any reason. I think that it is possible that this approach could sound even better than the direct romex due to the fact that the romex is not sheilded.