We had 2 months of 3-way jobshare at the end of last term, end of Y3 so mostly 8 year olds. 1 day / 3 days / 1 day.
One of the one-day teachers was the overall 'responsible' (due to being an in-house teacher whereas the other two were supply). So this is who we saw for parents evening. Which meant that when we asked questions the answer was often literally 'I don't know' (which makes sense, as this teacher had taught the class for a total of 8 days...). We never met the other two teachers.
I guess it can work well. In our case it didn't. Perhaps because it was only ever a stop-gap solution, it felt like none of the three teachers was really taking 'ownership' of the class. Nobody was able to answer questions. The two one-day teachers also swapped around their days a lot so we never knew when to try to catch the 'responsible' one and the other two would re-direct any questions to that one.
The children really needed some consistency and clear rules when this all started, which wasn't given. Instead, the more unruly kids played the teachers off each other and got away with blue murder. The quieter kids went completely quiet and invisible.The bullied child gave up asking for help.
By the end of the school year none of the teachers had built any kind of meaningful connections to most of the kids. Let alone was able to accurately assess them. Let alone provide them with work at their levels. The work the children were given was completely random. The end of the school year was a write-off.
Having said all this, IMO the reason it didn't work well in our case lies within the school leadership. To make this work, there should have been an information offensive IMO - so that the children and parents (and teachers, for that matter) know exactly who will be teaching when, what the arrangement is for subject-specific questions e.g. 'topic' on a specific weekday, does it stay on that day or move with the teacher when the teacher does a different weekday that week, same with homework due weekdays - if Mrs X teaches Monday instead of Fri this week, is homework still due Wednesday? Everybody incl teachers needs to be crystal clear as to how behaviour is dealt with, and stick to it. There can be no passing on the buck deferring questions/responsibilities to each other.
Also the school leadership ought to have strongly supported the three teachers in working together/coordinating. Instead it felt very much like they were just happy to be able to put a teacher in front of the class and didn't care about anything else. It felt like they had written off the end of the school year already and were just covering their minimal legal duty. Of course the teachers in this situation might find it hard to work up the enthusiasm to do all that extra coordinating work, unsupported and un-lauded, for a job they were leaving at the end of the year anyway...
So, if something like this were proposed for an indefinite term, I would expect some very clear information on how things will be organised, and if this were not forthcoming, I would be asking for it - not waiting for problems to arise and then not knowing who to speak to.
Some schools seem to be confident at this kind of information. Other schools (such as ours) treat the internal organisation of the school like a state secret ('No, I'm afraid I cannot tell you which days they usually have PE'; when the school library was silently abolished and parents asked which days their children would be visiting the library, the answer was not 'oh sorry we don't have a library any more' but rather 'I'm sorry, we can't tell you that' and similar...) so if your school is of the latter type, I would be very worried; if it is the former, it may well work.