Mark, the DOHC 750's were the natural evolution of the original SOHC, and politics had nothing to do with it. 
They made 10 more HP, and the 1980 models, which had needle bearings in the swing-arms instead of the plastic bearings used in the '79 750s and CBX, had handling as good or better than the best Ducati of the day. 
After that, Honda moved on to the V-4 bikes, like the Interceptor, and as far as I know, they still make motorcycles?
Absolutely correct on all counts! Especially the improved swingarms, which Honda changed bearing systems in no less than 8 times in the SOHC4 series.
The DOHC 750 was the same engine as the mighty CBX Six, with 1st-oversized pistons and only 4 of them. The DOHC 750 had the better alternator, though.
The first several years of the V Interceptor engines were a disaster, if you count what happened to them here in Colorado in the 1980s. They were found everywhere, parked on the sides of the roads awaiting towtrucks for things like broken transmissions, failed fuel systems, loss of spark and [some sort of] intermittent stray "handling" issue they seemed to have had. Once in 1985 our church bike club (about 30 bikes, more riders) had me and a friend of mine organize the first-every church motorcycle club ride (we did 4 per year after that until 1990). It went from Denver to Loveland, up the canyon and through Estes Park and Rocky Mountain Park, then south along the Front Range to Winter Park and Berthoud Pass, then I-70 back to Denver, about 350-ish miles of beauty. We started that day with 18 bikes and 22 riders, 4 of the bikes were the [then new] Interceptor V-4s, my CB750K2 in the lead, Johnny on his CX500 riding drag (we kept track of everyone via our CB radios on his & my bikes), the rest being Yamahas, a 1982 CBX (the cafe' racer one) as #2 behind me, some BMWs, a MotoGuzzi V-twin, and 2 Suzukis (I don't remember which ones, or all the rest of the bikes). By the time we got halfway up the canyon to Estes Park. one Interceptor shucked its transmission, being stuck in 2nd gear only, and one of the other Interceptors volunteered to drop out with him and escort him back to Denver. Neither made it home until a week later, on a trailer. A 3rd Interceptor got as far as Estes Park for Breakfast with us, but would not start afterward, we left him there waiting for a tow truck. The last Interceptor made it as far as Winter Park and overheated on Berthoud Pass on the way down (not up!) and opted to stop & wait for it to cool and was going to short-hop it back to Denver: he called for a tow truck later from Idaho Springs, instead. Two of the Beemers (2-up each) turned West at I-70 off Berthoud Pass road to come home over Squaw Pass (my all-time fave ride) and we arrived back in Denver with about half of those we left with, all the 'dead' ones being the Interceptors. Three of those 4 riders sold their bikes that following winter, 2 of them bought other bikes after that: thus was Honda's legacy following those days. I saw more than 7 more Interceptors sitting on the side of Denver freeways during my commutes to work in those days, a sad advertisement.
Then there were the [famous?] Hondarleys, which exploded on the scene here for about 5 years, after which they could be bought (still) for $1000 on average. The Gold Wings, of course, were (and are) everywhere in numbers here, even old ones, but they are hardly canyon-scooting rides. They do well on the interstates, though.
Update: this ride was in 1985, not 1982 (corrected above).
