“I was not eavesdropping,” Emma insisted. “I was tying my bootlace.”
The lace had come undone as she left the home of Miss Bates, a middle-aged spinster who lived with her elderly mother in reduced circumstances on the upper floor of a modest house. Emma had visited their rooms many times (though perhaps not so often as she ought). Never before, however, had the humble apartment felt so small. The Eltons had called so shortly after Emma’s own arrival that it was some time before she could with propriety effect an escape. “I paused at the base of the stairs to fix the lace. Could I help it that the Eltons emerged from the apartment and began their discussion on the landing before I had done?”
Mr. Knightley’s expression suggested that she might have secured the half-boot more rapidly had she wanted to. Sixteen years her senior, he had known Emma her whole life, and was as well acquainted with her foibles as he was with her charms. His dark eyes narrowed in doubt, and for a moment she dreaded an admonition delivered in his usual forthright manner.
I happened to read this excerpt in COCA and found the bold sentence very peculiar.
I think it here is a dummy used as a form object representing the that-clause. But I've never run across it being used with the verb help before.
What does the bold sentence mean? Is this usage common?