Ok, how about this?
An old mechanic told me years ago that if your motor had sticky valves, stuck rings or a lot of sledge in it, to do this. Drain the oil, pull the filter. Fill the engine and a new filter with ATF. Run it until it's warm, or about 1/2 an hour. Idle it, don't drive it. Then drain the atf, and pull the filter.
Put another new filter on and fill with your regular motor oil. I did it once to my S10's 2.8 carbed V6 and never had a problem with it.
I'd think with an IDI, you would want to do this with the motor already warm as a cold engine with thin ATF wouldn't make for a good coldstart. Plus you would only need to run it for about 10 minutes versus 1/2 an hour with a cold motor.
My two pennies, after I got my Peugeot I threw in 4 quarts of engine oil and 1 quart of ATF, drove it in the twisties for 45min-an hour, drained, replace oil and filter, that oil stayed clean for a while longer than usual.
I've tried the all ATF trick, not sure I'd try it again, I like slow cleaning.
Here's my plan on the new Mercedes, do 5 oil changes, one every 200 miles to slowly clean the loose junk and save a dollar, then Delo every 500 miles, I'll play it by ear, 2-4 changes, see how all that goes, then an AutoRX treatment or two, see what all that brings out.
I'd ask what you want to do before you use any treatment, many treatments claim to fill small scratches and pores, if AutoRX does what it claims then there will be no junk left in the engine to create these scratches.