Activist Board considering class action issue

What an activist the NLRB has become. It seems ready to consider finding a ban on class action claims enforced by a mandatory arbitration agreement violates the NLRA. It has solicited briefs on the following:

Did the Respondent violate Section 8(a)(1) of the Act by maintaining and enforcing its Mutual Arbitration Agreement, under which employees are required, as a condition of employment, to agree to submit all employment disputes to individual arbitration, waiving all rights to a judicial forum, where the arbitration agreement further provides that arbitrators will have no authority to consolidate claims or to fashion a proceeding as a class or collective action?

Pending case D. R. HORTON, INC. 12-CA-25764. Searchable here.