Cloche VS. Dutch Oven

I normally bake in a rompertof.  I find the crust comes out even in it, while the same dough split and baked in a DO has a very dark, almost burnt, bottom crust. 

and I also bake often in a steamed oven using Sylvia's super steaming method (rolled wet towels in old bread tins), but I don't bake in a DO, so I can't give you a direct comparison.  I can say that I don't vary anything (call that part process) up to the bake itself.  This works for me in my bakes because I generally cold retard my preshaped dough, so I can stagger the pull from cold to match my expected loading interval and so don't end up with over-proofed loaves.  If you don't cold retard this might be a problem for the third loaf when you bake one at a time, if you bake that many, or even for the second loaf if you have a warm kitchen and a lively yeast culture.

 As for the bake, my total baking time is pretty much the same for both.  I tend to leave the steam (towels) in about 3-5 minutes longer when using that method than the time I leave the lid on the La Cloche when using that.  Otherwise my bakes follow the below rough timeline in the oven.  The caveat is that, regardless of method, appearance and internal temperature always overrule the clock.

My bake timing for my sourdough loaves, be they round or oval, tends to be:

Pre-heat (body and lid both) La Cloche for minimum 45 minutes at 525F

Place loaf in La Cloche with Super Peel and replace lid

After 7 minutes at 525F turn down to 485F (I usually pop open the door for a 3-count to vent heat at this point)

After 5 more minutes I remove the lid of the La Cloche lid

Bake for 16 to 20 minutes, +/-, until loaf center temp reaches/exceeds 200F

At this point I take out the loaf and replace the lid on the La Cloche, and return the temp t 525F and set timer for 15 minutes.  My oven returns to 525F in about 9 minutes and I give the lid that extra 6 minutes to also get "hot" again.

My super steam bakes leave the tins/towels in for 10-12 minutes, while still turning down the temperature after 7 minutes, and the same total bake time, so it amounts to more time under steam.  For some reason the loaf seems to "set up" more quickly in the La Cloche than when using super steam.  I do not know why this is.  I just know these things work for me, in my kitchen with my oven and my... 

I tend to use the super steam method with as many as three loaves in the oven at once, when I bake three or more loaves.  It just takes too long to bake that many loaves when the total time per loaf in the La Cloche approaches an hour each.  I like the results I get from the La Cloche better than what I get using super steam though.  I also like my WFO results better. :)  In winter though, when the WFO is in the middle of the swamp that doubles as my back yard in spring and summer , super steam and the La Cloche work just fine.

Your burnt bottom crust means you need to turn down the temperature when you user your DO.  You could also try a couple sheets of parchment under the loaf to keep it from direct contact with the DO surface.  That might help by sacrificing the parchment instead of the bottom of the loaf.  I burned several loaves in my WFO last weekend in the same way you describe:  burnt to a black crisp on the bottom, so black I had to cut the bottoms off when I sliced them to freeze.

I hope it helps.

Bake Happy
OldWoodenSpoon

a Lodge, Le Creuset and Emile Henry. I do it the same in all.  Preheat oven with vessel inside to 475F, bake 30 minutes with the lid on and abo 20 minutes with the lid off or until it is the color you like.

The best way to find out is to do the same bread side by side. I would think they have principally the same effect and purpose. They both retain a lot of heat and provide a sealed environment for steaming. They are, of course, made of different materials, so they have different properties and values of specific heat, different shapes and therefore ratio of surface area to volume, etc. But it's going to be hard for someone to answer your direct question because you also have to consider that whatever the smallish differences, there are other things in your cooking environment that are probably going to make bigger waves. Every oven is different. I have double ovens and I find they are each different and depending on which of the two I'm using, I have to time things differently. And one Dutch Oven to the next is a little different...different brands may have slightly different thicknesses, for example.

So someone else's side by side experience, if someone has done such experiments, may differ from your own.