igdrasil, it does everything you need for timing control!
My original thread. . .(read the first page) states that you can control the timing not only by "knock" but also by rpm (with the mid-range retard control), as well as, by boost.
Let's say you're running 10 psi (for example)
You can set the J&S to pull anything from 0 to 2 degrees per psi of boost (there is a dial that lets you dial in 1/2 degree or 1.5 degrees - basically whatever value between 0 and 2 you want).
Now the next question is. . .what if I don't want to pull timing until I'm at 6 psi. . .NO PROBLEM! There is an additional dial that allows you to select the "start" from 0 to 10 psi (I realize I'm being redundant John

).
So, you could set it to start at 6 psi and retard 1 degree per psi from 6 to 10 psi (your max boost in this example). Thus you would have 4 degrees of timing retard at full boost.
The only "issue" is you can't take 2 degrees at 7 psi and 1 at 8 psi and 1/2 at 9 and 10 psi, but I'm not sure you would want to.
In addition there is the mid-range timing control. If you specify a rpm range you want timing pulled from (often your knock will occur at a specific rpm range) you can specify to have timing pulled at this range. So, in effect you can do something to pull extra timing at specific ranges if you so desire. This is setup on my unit to "ramp up" starting at 2.5 psi and being "full force" at 5 psi. That means there is NO mid-range timing retard if my boost is less that 2.5 psi! If I were pulling 5 degrees of mid-range timing (just to make the numbers easy) I would pull 1 degree at 3 psi, 2 degrees at 3.5 psi, 3 degrees 4 psi, 4 degrees at 4.5 psi and 5 degrees at 5 psi and above. Hope that makes sense.
The system has ramps so that you don't suddenly have a "stumble" when it tries to take timing out or put timing back. That would be hard on the engine and you. . .so it ramps the retard in and out.
John. . .I would be curious, since it requires "hard wiring" this feature, is there anything that can be done with the "Map limiter" adjustments so that you could make the midrange move or the amount of retard variable????? Just curious. . .I'd be happy to test it for you!
Finally, the "MAIN" safeguard feature. . .knock retard. If after all your timing is setup and you end up with a bad tank of gas, the J&S will pull timing when it detects knock. This is in addition to your setting and only used when the engine knocks. You don't set the amount of timing it pulls, it does this for you. You can set it up to pull timing on all cylinders or only the one that knocks (the unit can detect which cylinder is firing and thus which cylinder timing to modify). It does all this faster and better than a human ever could.
The knock retard does not occur at idle or low load, and ignores "noise" other than that detected near TDC. You cannot have knock on a cylinder when it is at BDC obviously.
Anyway, it is a very good piece of equipment for timing and safety. It cannot be infinitely programmed, but the way it is setup does allow quite a range of freedom in timing control. Now if John could "use" my suggestion above, you would have even more control! Hint, hint, nudge, nudge!
Let me know if you want me to call you to talk about this (anyone).