What can a stereo control plugin do that functions in a DAW can't?


I have the Alex Hilton A1 Stereo control plugin. I'm trying to understand precisely what a stereo control plugin like the A1 can do that one can't using pan controls in a SAW. I know there's other features in most stereo control plugins, but I'm only thinking about the stereo imaging aspect. I know it can pull left toward right in one motion with one knob, but could one emulate that sound exactly by using just pan controls? Would be grateful for some insight here.
It's basically a mid-side processor with a variable high-pass filter for the side channel. You can increase or decrease the stereo spread of a stereo signal while also making the signal mono below a chosen cutoff frequency.

There are some panning options, including dual pan and balance. Balance probably just changes the relative levels of left and right, while dual pan may move one side toward the other. For example, in balance mode, setting the pan control all the way left probably turns off the right channel. In dual pan mode, it probably moves the right channel completely to the left. I expect most DAWs could do these kinds of panning operations with the normal channel controls.

DAWs may have some kind of stereo width control, but the HPF on the side channel ("SAFE BASS") is a nice feature. Most DAWs can change the pan law. I don't know how useful the linear, log, sin/cos panning options are, except perhaps if you're automating active panning. The Fix MID and Bind M/S levels might affect how the panning works.

A plugin called TP Basslane does what the "safe bass" control does, but with the added benefit of being able to trim the level of the bass to compensate for differences in summing. If you have an EQ that can be applied to the mid channel, you can do the same thing. I find it's super helpful when you have a mix with a panned LF source, like a bass guitar.
Thanks for the reply. Do you have any thoughts about the quality of various stereo imaging plugins? The A1 seems to work and sound just fine, but I have nothing to compare it to.
I don't really use them. Regular panning is usually all I need. If I want to manipulate the width of a stereo source, I know some tricks for doing it without a plugin. But I do like the mono bass thing. I mentioned TC Basslane, but I just bought FabFilter Pro-Q 3, which can also do it.
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