It's been my experience that, at least for the major U.S. cable companies, the best support experience for the experienced IT professional is Twitter. The ISPs seem to staff their Twitter desks with people who have deep knowledge and a willingness to give a technically-adept customer the benefit of the doubt.
It also helps if you think hard about how you can describe your problem completely in one or two 140-character tweets. Generally, this requires knowing the lingo. A tweet that speaks the tech's own language gets more benefit of the doubt. Saying you're an experienced tech does little; way too many people think they know what they're talking about. Speaking intelligently about the technology used in the ISP's own systems identifies you as someone who Knows Their Stuff and cuts back on the scripted BS.
If your local cable company tends to send out trucks that say "contractor," you may want to get in the habit of asking them to send a genuine employee when you schedule a service call. The contractors are usually paid a flat rate per job, and so they are in a hurry to wrap it up and get to the next house instead of making sure the work is done right. I've found this to be a particular issue with Cox: if a contractor comes out, I will have to call back and get a supervisor out to do the work correctly, sooner or later.
Most companies have "executive office customer relations" teams nowadays, because people have figured out that calling the CEO's office when all else fails can be effective. Contacting the CEO's office, or the executive customer support team, is usually effective. I find it's best to sound a little upset, but not angry, when you make the call. The right attitude is "I'm really unhappy, and ready to jump ship, but I know you'd like to help me and I want to give you one last chance to make it right; can we work together on that?"
Sometimes, an executive-office contact will wind up giving you the direct number of a local tech supervisor or manager. That's pure gold, but you have to be careful not to kill the goose that laid the golden egg. Save the contact, but don't use it again unless (a) you're specifically told to call under certain circumstances or (b) you've already tried the normal support process and it hasn't worked. Yes, it's powerful to have the local head tech's phone number. It's even more powerful if he learns that you only call him when there's a real problem or serious communications breakdown in his organization.