Can Jedi use the power throttle

Too many unknown variables to know for sure.

Others have already mentioned that Luke was far from calm and was reacting to a very dangerous situation that he may simply not have thought about it.

The other unknown is how power itself affects rancor. In the movies, we've seen different creatures (and even different people) have different levels of resistance. Just before he fell into the pit, Jabba himself had defied Luke's attempts to outsmart him, and subsequent films show other creatures that are resistant (it takes some effort for Anakin to subdue any of the creatures in the Geonosian arena) to some form possessing immunity (Watto's species is immune to mental tricks).

My personal interpretation is that the ability to influence living beings is always in flux depending on the circumstances, which is why you don't see Jedi using their powers all the time (it would have been useful to control the Ewoks), and besides that large creatures that have more "life" due to their size are likely to be more resilient.

This interpretation could explain why most of the effects we see in the films are usually directed at inanimate objects (like telekinesis), while influencing living things directly is slightly less common (especially in the original trilogy, as both the power throttle and the the lightning bolt was also present as proof that Vader and Palpatine are extraordinarily powerful).

But it's just speculation.