I think this change should use openblas for lapack as well as for blas. Openblas has some lapack optimization but is also (at least in el6) based on a more recent version of lapack consistent with the non-tuned blas routines it uses. I don't know whether that might cause any real problem, but it can only be an advantage to keep them consistent and more recent.
Also, if the old libraries are required, I'd have thought they should be usable just by setting (R_)LD_LIBRARY_PATH, i.e. by a user and not requiring a system link. However, that won't work because of #1389719.