What I don't understand is how a lens designed to improve close vision can seemingly make long distances seem better sometimes - or is this just me perceiving it to be better? Wouldn't this defeat the object of multifocals?
For a simple and very small error in focusing, it's not surprising that a simple correction could make vision better at all distances. The shape of the lens in your eye is changed by muscles to be the right lens to focus on whatever distance you're looking at. A simple error in that lens shape changing can easily produce a consistent disparity between the correct lens shape and the actual lens shape, which would be consistently corrected by a fixed lens in front of the eye.
In any case, 0.25 is so small that it could be a placebo effect.
My eyesight is so poor (myopia and astigmatism) that apparently my uncorrected eyesight would qualify as "functionally blind", according to an optician who tested me. I'd certainly be rather limited by it, although I can see colours and blurry blobs just fine if there's enough light. Right now, for example, without my glasses I see a thin fuzzy black rectangular blur against a big yellow blob and a mostly blue blur inside the black rectangle with patches of grey blur. If I look carefully, I can see faint fuzzy black splodges on the grey bits. Far from blind, but rather limited in terms of visual functionality. I have simple lenses on my glasses and that gives me slightly better than normal visual acuity at all distances. No need for different lenses at different distances. Not yet, anyway. Probably will as I get older.
EDIT: I forgot the bit about multifocals. They're to correct a different problem, usually caused by aging. Prior to middle age at least, errors in vision caused by defects in the shape of the eyeball and/or lens are generally consistent at varying distances and so can be corrected at varying distances by the same lens. Short-sightedness, long-sightedness and astigmatism fall into that. Differences in focusing between short range and long range are a different problem and that's what bi/varifocal lenses are for.
So the lenses in your glasses aren't "designed to improve close vision". They're designed to compensate for the slightly incorrect shape of your eyeballs and lenses, which would improve your visual acuity at all distances. Close vision would probably be mentioned because people use and therefore notice visual acuity far more for closer things. "Small text slightly out of focus at normal reading distance" registers a lot more than "marginally less clear vision of that tree 100 feet away", even though it's the same reduction in visual acuity.
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