function removeBlockQuoteOnBackSpace() {
			// Add block quote deletion handler
			editor.on('keydown', function(e) {
				var rng, container, offset, root, parent;

				if (isDefaultPrevented(e) || e.keyCode != VK.BACKSPACE) {
					return;
				}

				rng = selection.getRng();
				container = rng.startContainer;
				offset = rng.startOffset;
				root = dom.getRoot();
				parent = container;

				if (!rng.collapsed || offset !== 0) {
					return;
				}

				while (parent && parent.parentNode && parent.parentNode.firstChild == parent && parent.parentNode != root) {
					parent = parent.parentNode;
				}

				// Is the cursor at the beginning of a blockquote?
				if (parent.tagName === 'BLOCKQUOTE') {
					// Remove the blockquote
					editor.formatter.toggle('blockquote', null, parent);

					// Move the caret to the beginning of container
					rng = dom.createRng();
					rng.setStart(container, 0);
					rng.setEnd(container, 0);
					selection.setRng(rng);
				}
			});
		}
Removes a blockquote when backspace is pressed at the beginning of it.

For example:
<blockquote><p>|x</p></blockquote>

Becomes:
<p>|x</p>