MKR CAN shield / MKR GSM 1400 combined use case questions

Hello everyone, I'm getting started with the CAN Bus shield for the MKR series. I have a few questions I'd like to ask about this module.

Is there separate documentation available for this shield? Arduino doesn't seem to cover anything regarding this other than pin-outs and the data sheet for the ICs in the module.

I was looking over at the available pin-outs in the module. I noticed there's 4, 2 for CANH and CANL and the other 2 for GND and VIN. So I took a look at the circuit diagram and found there's a TI buck converter, so I assume the function of this pin is to power the board externally?

Basically, it has the advantage that you don't need an external DC-DC converter for the VIN pin in the MKR boards? Am I right here?

That said, looking at the datasheet of the TPS54232, it specifies an output current of 2A. Does anyone have any experience in using this with the MKR GSM 1400? The store and docs recommend at minimum 2.5A available at least to maintain voltage levels during GSM handshakes.

But I've seen others use much less, and others use much more. Any help here?

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