DD1 is in Secondary Special School now, and I have to say that for her, it would be a disaster to be MS, simply for safety reasons. She has had so many incidents so far, already, in year 7, that have needed to be dealt with, and the thought of what they may have been in SS is just blood curdling.
For example, her site is secure, with CCTV. She still managed to climb over the school fence when she got angry with her peers at lunch time. She knew climbing the fence was naughty, but got very angry and wanted to get far away. Thankfully a teacher realised, opened the electronic gate and escorted her back in. When I spoke to the year head, their management plan was completely focused on learning why DD had felt the need to escape the playground (she was angry with peers) and combatting that, as well as preventing further episodes, rather than punishing her. They also did reinforce the rule of no climbing, and warned her that another time may mean exclusion (she didn't understand, so we said 'stay at home with mum').
Another child I know is at MS SS, has SEN, and walked out of the open school grounds after telling a teacher they would do so. That was not taken seriously, until the child was spotted by another member of staff outside school grounds. The proposed reaction was to punish the child because that was policy, despite the child clearly having no understanding of the impact of their actions.
Inclusive education, wherever it is, is about seeing the child and meeting them where they are. Not calling the child and expecting them to come to where you've called them to.