Is the ability to have single minded focus for ____ (grafting, archery, cooking, gardening, etc.) the fruit of meditation or do you believe that anytime that you can achieve single minded focus you are meditating?
*Every concious attempt* to keep your focus on an object *of your choice* is meditation. Therefor, training any skill is meditation.
The difference in training "just" meditation is, that you can put the sharpened focus you attain there *on any object*, no matter how interesting or dull it might appear to you. Meditation is the mastery of willingly directing focus and attention.
Is there a difference between concentration and meditation?
Hmmm, the first chapter of "The Mind Illuminated" deals with this question. As far as I remember, concentration (focussing your attention exclusively on a single object) lacks two things: Introspective awareness (things that happen in your mind/thoughts that arise while you do the task) and peripheral awareness (the ability to take in other stimuli in your surroundings). So concentration is a good thing, but meditation goes deeper.
Somebody who can conenctrate pretty well has mastered about one third of the way master meditation. But as long as the person does not get proper training, s/he is "stuck" on this level.