With a dynamic mic, it isn't a big deal. With a condenser, phantom power can be a problem with a trs patchbay. This is because for the brief time you are plugging it in, you are shorting things together and/or sending power to parts of the mic that should not get it. This is why mic connections on a 1/4 inch patch bay is generally a bad idea.
You also seem to be confused about the inputs and outputs on your gear.
If you have both a 1/4 and XLR output on your
preamp, they are both line level outputs. They just installed the two different connections for convienience. Do not confuse the type of connector with the type of signal it carries. As you saw in the video, both can carry a mic signal, both can carry a line signal.
The place you plug the mic into is the mic INPUT. The only
reason I point that out is because some people call all the connections 'outputs' and it confuses anyone trying to help. Since you were talking about a mic output on a mic preamp, (mic preamps don't have mic outputs) you were either calling the mic input an output, or calling the XLR line output a 'mic output'. I jusy wanted to cover both bases.