The International Existing Building Code maintains the nailed connection between the floor and the joists can resist 600 pounds per linear foot when you have a wood sub-floor with oak flooring overlay, and this is probably true. If there is reason to suspect this is not true, shear blocking can be installed on either side of the joist. A good Subfloor adhesive has a tremendous amount of shear strength. Many designers shied away from structural adhesive because they were worried about because the connection would be brittle. This means, just as is the case with stucco, once the failure starts it cannot be stopped. For this reason, this connection should always be over-designed so that the glued connection is so rigid there is no question of any movement at the glued connection. Modern adhesives will resist something like 250 pounds per square inch. If a 2 x 2 x 8 is used in a shear block you would have around 35,520 lbs. of shear resistance. Put that on either side of joist and you have doubled that.
