Answer: You can used three-wire bed joint reinforcement and loop ties only when the brick wythe and the block wythe are built simultaneously. When using either bed-joint reinforcement or loop ties it is important to make sure that the horizontal wire is positioned well within the mortar joint of the interior and exterior face shell of the block and in the outer half of the veneer wythe. I have seen several projects where the portion of the loop tie that is oriented parallel to the backup occurs in between the front and back face-shell mortar joints of the backup wall, rendering it ineffective.
Eye-and-pintle type anchors or other adjustable anchors are used when the two wythes are built separately. For example, the two wythes often are built separately in insulated cavity walls or when the outside face of the concrete masonry will be treated with a coating to resist water penetration. I prefer this approach because it reduces the risk of mortar bridges on the insulation within the cavity.
If the two wythes are built simultaneously and the insulation board is inserted every 24 inches on center, there is a risk of mortar creating bridges across the cavity. By building the concrete masonry backup first, insulation can be placed with the eyes extending through the joints in the insulation. The brick veneer then is constructed with a lower risk of developing mortar bridges.