Yes, Mr. Akin is simply reflecting the Church’s teaching regarding the total sinlessness of Christ (impeccantia) and His inability to sin (impeccabilitas).
Christ as a healer must have what He is going to share, i.e., must be fully, i.e., perfectly human and Divine or He could not heal us. He gives us the health, as it were, He has. If He did not have this health we, being sick, could not receive healing. So it is not Christ Who is not fully human, it is we, in our fallen state, who are not yet fully human. Only when we by His merits are conformed to Him by divine grace will our humanity be all that it should be. Christ is the Model and Goal for humanity, not vice-versa.
Christ has the fully human nature, i.e., one not wounded by sin. His humanity is therefore graced and in harmony with the Divine. For us to be tending toward sin is for us not to be fully human; therefore we are not the vantage point of healing of our wounded nature but He is. If follows that for Him to heal our infirmity He must bring health to our infirmity. We can’t give what we don’t have, so He must have this health of being fully human, i.e., in harmony with God in order to give it to us by grace. He therefore could not sin, which makes him perfectly human, not less human.
This from Ott’s Fundamentals of Catholic Dogma may help:
The Fifth General Council of Constantinople (553) condemned the teaching of Theodor of Mopsuestia, which asserted that Christ only becme impeccable after the Resurrection. It follows from this that He was already impeccable.
The intrinsic reason for Christ’s impecdability lies, as the Fathers stress, in the Hypostatic Union. Since the Word is the principium quod of His human activity, it follows that his human actions are actions of a Divine Person. Obfiously it is incompatible with God’s absolute sanctity that a Divine Person should be the responsible subject of a sinful deed. Further, the Hypostatic union effected an intrinsic penetration and control of Christ’s human will by the Divine Will.
From the Hypostatic Union there arises a physical impossibility of sinning and from the Beatific Vision a moral impossibility, that is, it involves such a close connection with God in knowledge and love that a turning away from God is actually excluded. (pg. 169)
For further insights into this, Our Saviour and His Love for Us, by Reginald Garrigou-Lagrange, O.P., would be very helpful.