Where are you located? Could you provide some history on the plant? -- how long you have had it, what kind of location you are keeping it, recent temperatures, etc.
My first thought was that those leaves look damaged from -- Sustained extremes like cold or sunburn, windburn....
...but If you suspect nutrient deficiency, then does that mean it's in a container and has been growing in it for some time? Has it been waterlogged?
...I don't know that it's a good idea to prune or take cuttings from a plant when it is visibly ailing... We should figure out what's wrong first. Depending on the issues, the cuttings may not be strong enough/have sufficient energy reserves to strike root and grow well. But if it's just a recent cosmetic damage, it probably won't matter.
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