The Paul-Barnabas Complex

Read some Acts. The missionaries Paul and Barnabas were a team. They had been through so much together: Winning many souls to Christ and receiving severe percecution. But in Acts 15 something happens. Paul wanted to check up on the churches they had planted. Barnabas wanted to take Mark with them. Paul had not yet forgiven Mark for deserting them in Pamphylia. "And there occured such a sharp disagreement that they separted from one another, and Barnabas took Mark with him and sailed away to Cyprus. But Paul chose Silas and left, being committed by the brethern to the grace of the Lord." (v.39-40)
I reckon it was a sad time for both of them. Nevertheless, was tis such a bad thing? Neither Paul nor Barnabas are mentioned to be in the wrong or in sin with their opinion. Could God not have instilled their disagreement within them for a greater purpose? The effect of this disagreement was that now 2 groups of 2 missionaries were traveling instead of 1 group. The Gospel was being moved rapidly over twice as much ground.
There are different opinions on how missions should be done. Some groups are humanitarian-focused, feeding the hungry, healing the sick, housing the homeless, and parenting the orphans, etc. Some, like the International Mission Board, are focused in taking the Gospel to those who have never heard. Some are focused in discipleship. These different opinions on how missions should be done have caused groups to go in different directions. The fact is, all of these types of missions are necessary in different parts of the Globe. God has seperated us for His higher purposes, and this can be a good thing.