One thing to keep in mind here is not all anemone species will behave the same or have same needs.
BTA's are the most common, so many people just group their experiences as the same, all nems wander, all that jazz.
This is not really true when it comes to other species of anemone.
I've been keeping anemone's for almost 33 years now, many species, and probably the last 8 or 10 years I've put my anemones where I'm pretty sure they will be happy, and I'm on a pretty good roll that all have stayed right where I placed them, but that was w/ LTA, Malu, which are sand dwellars, and magnifica, which given a proper perch up high not able to touch anything will typically stay put.
I actually scape my tank specifically for that.
BTA's, while most popular, and often called more forgiving as far as light and care needs, typically come w/ the offset to that as they just wander, often even after being good for a year or more in same place.
When it comes to BTA's, I don't think permanent is in their vocabulary!
I will not keep a BTA in a mixed reef w/ corals anymore for that reason.