FWIW the rat's nest of wiring on the bike I mentioned earlier was worst around the handlebars. Again there is a conflict; keep it all accessible so that it can be fettled/repaired or hide it all so that it is less easily damaged (but more difficult to repair/maintain, obviously). There are always wires somewhere that get flexed/vibrated and even well specified ones can still fail. I think that you are doomed to have exposed wires somewhere and these can get snagged.
One idea for mitigation of the snagging risk is to bind a reinforcement (eg braided nylon shot cord; in ~2mm form it has a breaking strength of something like 150lbs) to the crucial exposed wires using tape, and then tape the ends of the cord to the frame/handlebars so that in the event of the wires getting tugged, the cord takes the load, not the wires. Some wires are (modestly) internally reinforced with strands of cord anyway, but there is little harm in adding more reinforcement this way.
I'll agree with this principle. Having made my mistakes on other bikes, on my tourer (which has convoluted dynamo wiring for lighting with an inline switch, output for a charging device
[1], and wired computer with speed and cadence sensors) I've ensured that all electrical cables are securely attached to either a rigid part of the frame or luggage carriers, or tied to bowden cables for the run between frame and handlebars. The short loops where the cable has to flex to allow for steering or suspension travel are arranged to be in places where they're protected from being snagged on things. No problems with any of the wiring after several years, though I did damage a brake cable outer during a game of train-tetris once.
The most important thing is strain relief: Any appropriately-specced cable
[2] will withstand a decent amount of random abuse mid-span, but repeated flexing at connectors (or worse, absences-of-connectors) with tight bend radii will quickly lead to failure. The standard wired computer bracket with a cable emerging from the bracket at the handlebars and wandering off towards the forks is a prime example of what not to do.
Re 'staying in one position'; I have never found this a really good scheme. Once every few minutes I stretch, change position, ride out of the saddle or similar anyway, just to keep good circulation in every part of my body. Changing gear is just another excuse to move around a bit, so I don't begrudge it. BTW I don't find STIs especially comfortable to use (maybe back to the wrist thing?) and in many ways prefer a standard gear lever mounted somewhere handy.
Recumbent riders are the experts on this: Given a sufficiently comfortable position that isn't messing with your nerves or circulation, you can easily stay in it for a couple of hours. But at some point you're eventually going to want to move around. If I'm riding continuously (bike with no stopping at junctions, or trike) I'll usually stop for a minute or two once an hour just to be able to bear weight on locked-out knees (which you don't get to do on a recumbent) and flex my back a bit. Usually that's combined with an opportunity to eat something.
On uprights this isn't a problem. You can ride out of the saddle for a bit to give the knees something different to do, and since you're continually shuffling around to try to balance hand/wrist/neck/arse/genital pressure, you don't get the same stiffness.
Anyway, none of that changes the obvious advantage of easy-to-get-at controls.
[1] On the basis that the best place for delicate things like battery packs and USB connectors is safely inside an Ortlieb with a single robust connector (on an easily-replaced cable) to quickly disconnect from the bike's wiring loom, rather than strapped to the bike where they can get wet/bashed/nicked. I accept that endurance racers will have a different set of priorities to tourists here; if nothing else they want things where they can see that they're working.
[2] I reckon Schmidt have the right idea in favouring coax over figure-of-8 bell-wire, even if termination is more of a faff to do neatly. Where you have a choice, highly flexible rubber or silicone cables (think multi-meter probes) are going to be a lot more resilient than standard PVC coated wire.