I've certainly come across the magic number seven plus or minus two before, in study of simultaneous interpreting. The interpreter is usually a sentence or two

I've certainly come across the magic number seven plus or minus two before, in study of simultaneous interpreting. The interpreter is usually a sentence or two behind the speaker. The trick, they say, is to increase the size of the chunks, as you can't do much about the number of them. Try to process a sentence in clauses, not in words. (You need to do that anyway, really, as the grammar of the languages may not match up.) I suspect that something similar applies here.