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This is a sign that the plant is under some kind of water stress. Typically for yuccas, this would mean too much water but given your location, it may be too little water. Check the roots just to make sure there is not root rot (which would prevent the plant from taking up water) and if the ground is very dry, give it some supplemental water.

This article will help:
https://www.gardeningknowhow.com/plant-problems/environmental/what-causes-brown-edges-on-leaves-of-plant.htm

If they are very large, I would suspect that they may be root bound, which would cause brown edges on the leaves. This article will help you determine if this is the case:
https://www.gardeningknowhow.com/plant-problems/environmental/root-bound-symptoms.htm

This article will help you:
https://www.gardeningknowhow.com/plant-problems/environmental/plant-leaves-turn-yellow.htm

Yes, you can actually. This article has directions for doing that:
https://www.gardeningknowhow.com/ornamental/foliage/yucca/yucca-plants-care-and-pruning-tips-for-pruning-a-yucca.htm

The reason you have read conflicting advice on over and under watering is because they have the same effect on a plant. It can be confusing to determine.

But, with yucca plants, typically they are over watered because they are a desert plant and people tend to care for them too much. Water only when the first inch of soil is dry.

Even if you do properly water most of the time, one time over watering can cause root rot to set in and that will also cause symptoms like that. Here is more information on root rot: https://www.gardeningknowhow.com/plant-problems/disease/treating-root-rot-gardening-tips-for-housplants.htm

I would look to either over watering or root rot as the issue at this time.

A balanced fertilizer will work fine. Fertilize it about once every 3-4 months.