I am on it and I am at it--Jeff, Sir please clarify
If I say "I am on it", then "it" is a problem that needs solving, or a task that needs doing — but it's something finite. I'll be finished doing it, sooner or later.
If I say "I am at it", then I'm doing some job, but there might not be an end in sight. It could be something like "doing housework", or "earning money", that isn't ever going to be finished.
This is not a distinction that I use, but it seems logical.
Americans are more likely to use "on it" for either sense, and "at it" has a slightly British feel. I suspect that the usages you describe are more prevalent in British English.
Your's is a perfectly good distinction, and I would not discourage its use.
|link||answered Jul 19 '12 at 21:02 Jeff Pribyl Grammarly Fellow|
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