Going out on a limb here. I don't rate Mary Berry very highly. I've watched a few episodes of the Bake Off thing and while I Iove Paul Hollywood, now there's a man who knows his bread, Mary Berry seems to me... well average. I'm sorry but I don't understand why everyone thinks she's such a fabulous baker. Baking margarine and putting all ingredients in the mixer all at once with added baking powder! Really? It's like calling someone who uses a bread machine a master baker. That's not to say I never use the all-in-one method; some cakes call for it but to do it for every cake it seems like a bit of a cop out to me. And I'm pretty sure that most people who do bake cakes as well as those who really like to eat homemade cakes can tell the difference between an all-in-the-mixer-together cake and a one that's made by creaming butter and sugar together, adding the eggs and beating until thoroughly combined before folding in the dry ingredients. I can. The first one tends to have a denser crumb and can sometimes be a bit doughy.
I know I probably sound like a purist here but to me, putting everything in a mixer is only one step removed from using a packet cake mix and I'm sure you all know how I feel about that. Equally, I'm the first to admit that there is a place for both - all in one and packet mixes that is - but really, Mary Berry a cake baker who judges others' efforts! Am I missing something?