In order to entice professionals in other fields to become teachers, there has to be some pretty good incentives for them to leave their other job.
Besides getting paid to study, which is a good thing, you would reasanably expect to be offered a permanent job somewhere at the end of it all. After all, you wouldn't leave your secure job as an engineer only to be given consecutive contracts for a period of time right?
So lets say that of these people switching professionals will be given permenancy. We have also established that this program will not suit everyone, and you are probably going to get a mixed bag of people that actually swap professions (i.e. some good and some bad). This has the potential to add bad permanent teachers to the pool (and im not saying that these don't exist already).
There will need to be some kind of assessment process (as there is now with student teachers) to ensure that these new teachers are up to certain standards, otherwise we will be adding some permanent teachers (read: hard to get rid of) who aren't up to it.
Given that this assessment process is a must, are you then less likely to quit your job as an engineer, do all of this study when there are no guarantees about a job at the end (only if you met certain standards?).
I come back to my point of offering greater incentives for young people to get them to study undergraduate degrees in teaching in the first place (having said that, it then takes 4-5 years for these people to get into the system).
(and by the way the 18 month teaching course was a degree, now a masters in education, not a diploma


