Hi,
A more technical comment. According to Jeff Schewe LR presharpening is pretty similar to PKS but with more control for the user and the sharpening algorithms are more refined. The additional refinement is coming from a close cooperation between code developers at Adobe and the Pixel Genius folks.
Regarding the sharpening for output there are a couple of advantages.
1) The sharpening should be applied when the image size is known, LR knows the image size, no room for mistakes.
2) The image could be resampled before printing, but this resampling is on the fly in LR
3) The resampling algorithm in LR is a Lanzos variant and is arguably better then Bicubic softer in PS
Best regards
Erik
Erik, it would be good to hear from Jeff on this, meanwhile thoughts on your three points:
1) PK Inkjet Output Sharpener in Photoshop reminds you of the pixel dimensions and you select the sharpener accordingly. One can make mistakes but (a) this seldom happens in the hands of careful users, and (2) if it does, it isn't necessarily a train-smash. It is also nice to know that once the sharpening is done you have flexibility to alter its strength using the layers it creates.
2) If LR is resampling on the fly to print, one wonders whether the sharpening is also adjusted on the fly, or whether the sharpener sharpens to a known stable output resoution. Here is where Jeff may be able to help us.
3) Resampling is a separate issue. Normally, I don't resample to print, but if I need to, it is most often downsampling to smaller file dimensions in which case one would use Bi-cubic sharper in Photoshop, and this works very well.
Mark