Slightly off topic but! I was a Service manager at a Chevrolet dealership when the 700R4 came out and we had about a billion transmission fails. I don't know what has been done to your transmission but I would strongly recommend that you never use the OD if you have any kind of load or are in hilly country or even in a strong headwind. That transmission will kick into and out of OD about 60 times a second when under a load. As with any other OD equipped transmission it nearly always better to not use the OD during in town driving. They work great on the highway so long as your not running up and down mountains. They help the milage a bunch on mostly flat highways. It sounds like your going to have a great rig.
I don't know where you got your information but from a dealership, I can guess.
The early 700s had parts failures and were basically a field test for GM to see how they stood up in public hands - but to say that the OD would "shuttle shift" (that was the factory official term for that problem) 60 times a second is not only a lie, but physically impossible.
Shuttle shifting was a mistake in terminology and a malaprop - but a dealership wouldn''t know it because what happened inside a transmission, for a dealership - was black magic and wizardry and although a dealership had the best possible training available from the factory, the dealers wouldn't let their "technicians" go for it because it cost the dealership the money it needed to keep the hot-n-cold running secretaries in the owner's office suites.
There --- now I've made a generality too - just like you.
Back to the whole truth --- leave the transmission in OD and let it work as it is designed --- I've seen too many units come into my shop where the owner would shake and turn white if I told him it was to be used and the only time to use a lower gear was (mostly) for engine braking --- and at those times when dropping into 3rd/Direct was somewhat easier on the engine as you could keep it in it's best torque-range for better driveability.
In the early-to-mid 1960s, the automotive world was still coming out of some really bad post war engineering and OD was a weak gear that shouldn't be abused --- on most vehicles to date. But statements like yours were inflammatory and although it sounds like the ignorant things that were said about vehicles, it was just bald-faced lies and poor understanding of the magic and mysteries going on inside the transmission.
For the record --- besides being the owner/operator of a few (3) auto repair shops (I also owned and operated a couple (2) of independent transmission shops in SoCal, where from 1962 I was a BAR/Cal-EPA Inspector and Brake-Lamp & Smog Inspector/Installer/Adjuster)--- I made my living correcting bad theories and ghost stories told by incompetent "mechanics" who were still stuck in the 1950s haywire-and-friction tape era of technology.
So don't go blowing all the "60 times a second" dealer-talk around; it's just bad for the industry and really shows some people as being truly ignorant about things-mechanical.
I own/drive/tow a 3-cord logging trailer behind ---> and generally mistreat my own '86 K5 with a stroker 383 and the THM700R4 transmission in it is the one I rebuilt over 30 years ago and you can bet that I use OD constantly.
That said ---->what I DON'T use all the time is: TCC - which I control from a rocker switch on my center console. I have destroyed the sprag once before with a high RPM/WOT shift and I'd like to avoid that.
I'm gonna copy/paste your post and email the .pdf to a buddy who's still in the transmission business - so he can display it in his shop.
We'll Zoom-laugh over a Dos Eques over that one --- 'cause we thought all you pre-boomers were dead by now.
