The entremets I made the other week I had to weigh out egg yolks for the mousse. That might have been a weigh too far.
ISWYDT
However, not as silly as it sounds.
A good few years ago, I realised that even modern cook books still use eggs as they were in the 1950s, where as the eggs in my store are modern large size. I only managed to make decent choux pastry when I wrote on the recipe in red pen "not this much egg" and did it by perceived texture not number of eggs.
Same sort of thing with victoria sponge.
Cook book writers just copy historic ingredients lists over an over.
I always assumed the american use of cups was because the pioneers didn't have scales.
You would have thought they would have made a bit of progress by now...
I commend the book Muffins by Susan Reimer. She not only gives US/UK conversions charts, but explains why american flour is not the same as UK flour...
Sadly, my cooking does not have the ambition to make entremets....