Some pastors who believed the WELS was sinning in this regard left the synod. Others who disagreed did remain within the WELS.
At the New Ulm, Minnesota, Pastoral Conference on September 25, 1957, Pastor Paul F. Nolting delivered this essay on Romans 16:17.
Some notable quotes near the end of the essay:
"Where in God's Word does God give us the right to disobey NOW because of the possibility of change in the situation of the FUTURE... But that hope within me dare not prevent me from obeying a specific Word of the Lord that applies NOW... If love becomes the grounds for disobedience, then such love is not from the true love of the Word and of the brother, but a love which springs from the flesh and is of the devil. To obey always has been, ever is, and always shall be better than sacrifice. Our God says, 'Mark and avoid.' He does not say, 'Mark, wait and see, live in hope, and if at length all fails and hope is finally extinguished, then resign yourselves and avoid.'"
September 25, 1957 Paul F. Nolting Romans 16:17,
(warning: dust off your greek lexicon!)