As Paul said, "I have become all things to all men, so that I may by all means save some." We should use all means to save some.
Some will be put off by an invitation hymn and an altar call. Others will be put off by the lack of one. I agree with the author that the Scriptures do not enjoin one, neither however, do they forbid one. This is the old "I am of Paul, I am of Apollos" partisanship.
Doesn't it boil down to the fact that it doesn't matter how they come, as long as the come?
I am quite sure that many altar rail conversions are pure emotion with no real commitment. Likewise, I would think that many appointments in the Pastor's office would lead to a "commitment" if for no other reason than to end the appointment.