As a member of Microsoft support team who works with mailbox moves a lot, I wanted to add a few thoughts on this subject. We know that this CMDlet has been used to temporarily solve issues. Fact is that moving mailboxes around the datacenter with the hope to find a ‘better database’ or a ‘different server’ which might temporarily fix a particular issue is definitely not something that we expect (or want) our customers to do. Engineering and support want to be aware of issues so that they can be permanently addressed. Also note that if you move mailboxes around, the event history data might be lost so we, support, can't analyze things and tell you what went wrong in the first place.
That is why it is important to call support and ask for help.
I am sorry to hear about poor experience with us, support team, but we are trying to do our best. We also need time to understand your issue so when you talk to us, we need to collect data and do troubleshooting before trying to fix it. We know that before engaging us, you already spent some time understanding the problem and testing it thoroughly. But have patience with support, we are helping both customers and engineering when customers engage us, and the fact is that vast majority of our customer interactions are solved once we learn what is really going on.