Originally Posted by Douglas
is that even true?
here is my understanding of how the oven works: it has a thermostat. when the temp falls below the preset level, the oven "lights the fire," so to speak. I presume that most ovens are two-state; that is, they are either on (fire is heating the oven) or off (fire is not heating the oven, temp is theoretically held even, though of course you are losing heat to the food and also to the outside environment). There isn't a "halfway on" or "hold temp" state.
Larger things take longer because the heat has to "soak in" to the middle to fully cook the center, but multiples of equal size, while requiring more heat, will just mean that the oven is "on" for more of the same time period?
Anyways, not trying to start a nit-picky e-fight - just trying to learn more. Obviously you are the expert, not me... but I like to understand not only what happens but why it happens - so that I can expand beyond just having a point fact, rather understanding the concept more deeply.
Edit: as Fang66 points out, what's more important than the quantity is how much that quantity resembles a single larger mass rather than individual ones.
I think you are mostly correct about how the oven works (and fang is correct about crowding being more important which will be the big issue unless you have a huge oven).
I think there is some effect though. The cold items in the oven should have a heat sink effect so I would assume that the speed of the on/off cycle would change.
The oven will heat up to its upper limit but then the extra mass of meat will cause the oven to cool faster than it would normally which brings the oven back down to the bottom of the range and has to kick in the heating element again. My guess is that the "ideal" temp is closer to the top cutoff than the bottom cutoff since you probably don't want to get much above the set temp, but you figure the latent heat *should* hold for a while on the way down but for the extra meat.
It wouldn't make a huge difference but 5 minutes sounds plausible. The big issue really though is going to be the pieces of meat insulating each other. Even if they aren't touching, they will block any radiant heat and the tightly contained air will act as an insulator which will keep everything from cooking evenly.