The latest version of 'The Art of Ministry Training', the 'how to train an MTS apprentice' course has recently been released. Col Marshall, former director of MTS has spent a long time working on this stuff and the new edition is a vast improvement.
It is easy to summarise a movement one particular way, and not make allowances for the fact that over time, the movement learns and adapts. It develops nuances and subtleties that answer earlier criticisms. And so with MTS, it is easy to criticise it for what it *was* ten years ago, or how it is *implemented* by one pastor in one place. The movement as a whole, however has moved on.
Early MTS was pretty gung-ho in dismissing any concept of a call to ministry. The gospel itself is the call to ministry, any other 'call' is unbiblical mysticism. The only questions we should be asking about paid minsitry are more practical ones such as giftedness and godliness.
In the latest version of AMT, there is a more nuanced approach, by equating 'call' language with
'sending', 'appointing' and 'stewardship' categories:
Given God's call upon all his children, it is clear that God also 'calls' particular servants through whom he revelas his will and purposes to his people. God calls or sends or appoints [emphasis mine] particular ministers to proclaim his Word and lead his flock. The distinctive of this ministry to which some are called and appointed is in stewardship - the degree of responsibility...
The Bible does not speak in terms of an inner call to ministry. The call comes from God through his ministers and by the recognition of the congregation. However there are some passages which touch on the personal response. The desire for the ministry of oversight is commended because it is a good work....
Calvin taught of a secret or inner call but this does not seem to be a mystical experience but rather a burden for the ministry deriving from godly motives as reflected in 1 Peter 5:1-4... and then the Institutes are quoted.