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There are lots of claims of achievable no. of lp/mm but funnily I can
never see numbers published for a film that is actually on sale.

Perhaps because it's not that important or relivent to film, in the same way you don't see the grasin size mentioned when talking about high ISO in DLSRs it's called noise now. I don't remmebr buying HP4 or 5 or kodachrome having a noise rating funny that. Perhasp because they didn't priduce noise..

Grain size is dependent on the development procedure. Of course one doesn't hear grain size mentioned on dslrs. That because they don't have grain. They have noise instead which is a different beast entirely.
Equally film doesn't have noise as noise is a by product of digital processing so how in heavens name would they have a noise rating.

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.is one advantage not having a pentaprism and mirror
combination, it unties the hands of lens designers, leading to simpler
and more efficient lenses.

Lens designers have always strived to improve their designs.
pentaprism and mirrors have nothing to do with that.
most P&S and compact cameras didn;t have pentaprism and mirrors,
but they also didn't have interchangable lenses.

As stated before the absence of the mirror box gives a lens designer much greater freedom in his design choices

But for the camera manufacturer the absence of the mirror box and pentaprism eliminates two of the most precise parts of an slr. One of the reasons dslrs will eventually disappear. Once the evf reached satisfactory resolution any benefit of the mirror and pentaprism were gone.

Now one can see in the viewfinder a true representation of what will be captured. No more chimping to check the shot. Exposure and colour rendition can both be checked before pressing the shutter button. Workflow is much faster now one doesn't have to keep checking the captured image. Faster 'motor' speeds can be achieved with continuous viewing as there is no mirror to flip up out of the way blocking the view.