shabbat - How does Shabbos/Yom Tov mode on a stove work?

Star-K certifies the shabbos mode on some modern stoves. (Oh how I pine for the day of simple rheostats on electric stoves, and pilot lights on gas stoves! Those were the days...)

Our GE gas stove bothers me.

Shabbos mode is basically disable the 12 hour auto shutdown. No big deal. I get that one. I hate that the stupid device beeps every 3 minutes (with a ear-shattering kaboom (oops, I meant beep)) forever, till you hit the button. (My mom and I discussed just cutting the connection to the Piezo noise maker in her electric, but were informed that would invalidate the warranty).

Yom Tov mode bugs the heck out of me, and I want to know why this is allowed.

You set it into this mode (some silly keypress sequence) and the temp display is turned off, but it stays where you left it temp wise. Then the up/down temperature buttons now cause a 15 degree F (not sure what happens in Canadian stoves. 8.3 degrees C? I guess they jump 10C at a time for cleanliness), but not immediatly, at some random time in the future.

No beep, no display changes, no immediate reaction. But in the next couple of minutes (randomly I am told from the manual) it will change.

I assume this a level of Gramma issue, but it really bugs me.

Perhaps a corralary to this question (Will ask separate, but worth considering) is the Shabbos mode powered scooters. If they delay the responses, seems like a death sentence. Heading to a street, light is red, you hit stop, and it randomly delays? Seems ill-advised to me!

Answer

You're not clear about what, exactly, bugs you regarding the Yom Tov mode. There are two aspects here: The fact that you are causing the oven to operate, and the pressing of the buttons that provide information to the oven's computer. Rav Heinemann has a teshuva (link) explaining his reasons for permitting this. Very briefly, the causation aspect is not an issue because this kind of Gramma is allowed on Yom Tov; and the button pressing is okay because there is no visible effect, and the Torah does not forbid things that are undetectable to humans. (See there for why this would not apply to computers and recording devices etc.)

However, many other poskim -- notably, Rav Shlomo Miller and numerous authorities in Eretz Yisrael -- reject this position (I think mainly due to the second aspect mentioned above). See here. See also here for a detailed article about this controversy.