Regularly the question comes up whether it's better to apply sharpening of an image in the RAW software or to do all the sharpening on the finished images.
Of course, if you leave the finished file at the native pixel size there's now drawback in sharpening at the RAW stage.
But if there is any kind of resizing (up or down) I'd say it's better to process the images without sharpening initially if the best possible print quality is what you are up to.
Here's a comparison of a small crop from a P45 resized 250%… so the actual print of the entire image would be 150x115cm.
The upper image was sharpened in Capture One with the preset "Version 3.7 soft look".
From the list of presets this is the least aggressive sharpening C1 provides (of course you can set any other values but "Version 3.7 soft look" is indeed not too heavy for this file).
The image below was processed without sharpening in C1.
Both were uprezzed by 250% with "Blow Up 2" (Alienskin) which is my preferred scaling tool.
I left the (pre-sharpened) upper image without further sharpening.
The image below was sharpened on several layers (basically a multi step sharpening with different sharpening settings for surfaces and edges).
There's no noise added or other nice things that may help to create a pleasant look for a large print. This was done quite quick and rough (and it is rather screen sharpening than print sharpening).
Afterwards I downsized the images 32% to match the print size on my monitor. My monitor is 24'' with 1920x1200 pixels so at 32% zoom the monitor image represents exactly the print size at 300dpi.
The comparison will of course not show accurately what the actual print will look like but it will give an idea of what this comparison is about.
IMO you can clearly see that the image below (so the one without pre-sharpening) contains much more details… it simply looks finer, more structured, richer.
Of course I could have applied additional sharpening on the upper image but that would look even more coarse.
If you move back 2 meters from your monitor you won't notice any real difference anymore. But if you look from about one meter distance - which is a bit close for a print at 150x115cm (on the other hand not really too close) - there is a noticable difference.