What are you trying to find out? It may be good to work with your partner or Aruba SE to explain your use case.
In general, your performance will decrease by limiting features. It's always a trade-off between the available 'airtime' and the single-client/multi-client overall performance. If a client connects with as many streams as possible, the data is transferred faster and your 'air' is free again for other clients. By limiting to 1x1, you will in practice end up with leaving airtime unused. Unless you have a very specific scenario where that is not the case. Also, note that MU-MIMO only works for clients that support it which is at the moment far from all clients. AirMatch/ClientMatch has the intelligence to group clients with similar capabilities to optimize this in an automated way much better than you probably can do this in a manual way, in practice. It's fun to have theoretical discussions, but for that, it is important to understand your exact use-case and assumptions. Having the discussion interactively with your partner or Aruba SE seems better than on this forum. If you end up with a conclusion and questions following that conclusion, it may be good to post it here or get it checked internally with people like Jerrod.
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Herman Robers
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If you have urgent issues, always contact your Aruba partner, distributor, or Aruba TAC Support. Check
https://www.arubanetworks.com/support-services/contact-support/ for how to contact Aruba TAC. Any opinions expressed here are solely my own and not necessarily that of Hewlett Packard Enterprise or Aruba Networks.
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