I thought it here, and it came out there.
Did Almighty Bob send you your Sandwich Maker in a scary, but dramatic burning chariot, or in a more mundane, but safer non-burning one?
You guys have never tried cooking it without flattening it, have you? The grilled cheese doesn’t cook evenly if you don’t flatten the bread. Since bread isn’t perfectly flat naturally, just throwing in on the pan results in part of it (usually one of the outer edges) being toasted to black while another part is still just covered with barely melted butter.
Mmm, squished cheese.
In food service situations with grills that don’t have much of warmer/colder spots, it’s so much easier to finish the bread and the cheese at the same time if you can squish it down with hot metal.
If the bread is fluffy, then it will brown without the heat ever making it in to the cheese. It’s like any insulation, the pockets of air prevent heat transference.
iow, You have to smoosh it to make the cheese melty.
You have a very weird frying pan. I’ve never squished a grilled cheese sandwich and it cooks quite properly, and evenly, without said squishing. The cheese also melts quite well and gets stuck to the bread just fine. I don’t think I would like one cooked that way. It would lose the nuance of texture, the crisp/soft/cheesey/soft/crisp stack so perfectly balanced it needs no improvement.
If you can’t cook a grilled cheese sandwich properly, without using a squisher, you don’t know how to cook. 
Having said that, using something hot on the top helps cook the thing faster. This is the primary advantage for a short-order grill cook.
ETA: btw, a good grilled cheese sandwich cheese is raclette.
My electric griddle makes awesome grilled cheese without squishing, the bread is browned to perfection (except when I forget how long it’s been down) and the cheese is marvelously melty and I even use two slices of cheese.
[Let the ridiculing begin.]
I butter both sides of the bread and place them side by side on the griddle. After the bottoms are toasted, I put the toasted sides with the cheese in the middle and toast the outsides. I like the bread toasted inside and out.
You don’t have to squish it down. Sometimes I’ll put a pot lid over the sandwich n the giddle. It keeps the hot air in and helps melt the cheese.
Absolutely. On the outside, it’s the fats that make a grilled cheese great. Mayo (not salad whip, or whatever it’s called), has a great tang, that works great. The eggs in the mayo give it a bit of a savory french toastness on the outside.
I forgot that I had learned it from his show, but yep, it’s basically Alton’s system. The mayo is for flavor, I don’t get the same satisfaction from margarine on the outside.
Confession: I use butter/margarine on the outside and put mayo INSIDE with the cheese. Double whammy! And to preempt the inevitable: yes, the sandwich still sticks together.
I used to do the margarine-out-mayo-in trick with fried egg sandwiches (with cheese). What a great stack of death: margarine-bread-mayo-cheese-egg-cheese-mayo-bread-margarine.
That does look like a good choice. Personally, I find that Colby and brick work very well, too.
That’s what I do too. I start my sandwich off open faced and find that doing it that way combined with cooking at a relatively low heat (which gives the cheese opportunity to melt without the bread burning) and keeping the pan covered while the first side cooked, I end up with beautiful grilled cheese sandwiches and have never been tempted to flatten. Once the cheese is melted and the first piece of bread is browned, I add the second slice of bread directly on top of the melted cheese, it sticks, and I flip the entire sandwich. The rest of the cooking is done uncovered to keep the top slice of bread from losing any crispiness.
Don’t worry: most of my grilled cheese sandwiches end up with more cheese than bread by weight. I think the one-slicers are odd.
Cool. I was expecting to have abuse rained down upon me for using cheese slices at all.
I thought of this thread today when I was making a grilled cheese! 
The bread kinda went concave on me and I couldn’t get it to brown in the middle, so I smushed it with the spatula.
Why bother with slices when you can just use Cheez Whiz? :eek:
I’m sorry, but you people must be working with some tremendously inferior bread and/or cookware. Either that, or you’re terrible cooks. I’ve never had either of these problems in my life.