I think the tissue visualization is a helpful exercise, but stopped doing it after a while.

But even now, I sometimes catch myself moving too much rather than keeping things simple and straightforward and have to get myself back into the right mindset. A little Clarke 1 and 2 on passive air at a soft volume usually helps me a lot.

I would add to Xandar’s recommendation that do what sounds good AND what’s most efficient–these are really the same thing, once you find optimal.

Harmonic slurs, for example, used to be something I powered through like it was an endurance exercise, which it is helpful for endurance; but to really get the full benefit, in my opinion, one has to experiment looking for the easiest way to change pitch as that’s the most efficient AND happens to sound the best as well, which ultimately what playing is about–if we can find the easiest way to produce a given pitch, we’ll have more control, endurance, flexibility, ease of articulation, etc. If it takes everything we have just to touch the pitch, then we’re going to be very, very limited.

Learning to cooperate with the air, not fight the air, is the key.

That’s my perspective, FWIW.