Elder Faust once told leaders not to let the handbook and general guidelines keep them from receiving the inspiration to which they are entitled and which they need. We need to be able to recognize exceptional circumstances and act properly therein, since those exceptions are meant to include good people who otherwise might be excluded.
However, I also think that imposing a general standard or practice not required by the handbook and general guidelines (like requiring every single young man to have a missionary haircut in order to be ordained a Priest or pass the sacrament) is not seeking inspiration outside of the handbook for unique cases. It is a systematic and practical change to the handbook - and I discourage that without exception, since doing so automatically excludes good people who otherwise might be included.
That's a major difference, and I believe recognizing that difference is an important part of charity.