What is a "useful grasp" depends, of course, on the task in question, but common to many tasks is the requirement of grasp stability.
There was marked bradykinesia of finger movements in both hands, and the left hand had no useful grasp.
When we go to museums we're given a lot of facts about things – their dates, materials, subject matter (if any), the cultures that produced them and so on – and these specifics are often useful in helping us grasp the basics of what we're looking at.
It is this autonomous realm that history, literature, and the rest of the humanities help us grasp — indeed, in ways that may prove useful to Darwinists in their attempts to model social reality.
But loads of experimentation and learning is already propelling us towards a more realistic grasp of where/when PbR might be useful and how it needs to evolve, much faster than the comparable curve for, say, microfinance.
A grasp of Italian comes in useful: there were no other British campers at the site when we stayed there in August.
It is very useful if the unsaturated horizontal seepage behavior in the ground and the grasp of the water movement can visualize.
Some key recent developments have furthered the "second industrial revolution", making 3D printing more useful, expanding its possibilities way beyond simple plastic trinkets and putting it within the grasp of anyone with an interest.
This seems like a small thing, but as someone who spent a decent stretch of time in Japan without anything beyond the most basic grasp of the language, I can attest that it would be very useful in practice.
Visual illustrations may be extremely useful in providing examples and non-examples of analytic concepts, thus helping to sharpen our grasp of those concepts.
