What's wrong with using the whiz wheel in flight? It's no worse than writing clearances, a nav log, the occasional plotting task, studying an approach plate, using a checklist etc
I don't think that's a fair comparison. Writing clearances or looking at a nav-log or checklist requires very little attention, compared to lining numbers up accurately on a whiz-wheel. I'm not sure what you mean by "the occasional plotting task" - if I need to divert I may draw an approximately straight line roughly where I'm planning on diverting to - again, a task which doesn't demand much attention - but I wouldn't want to do much more than that in flight. I would always study approach plates for my destination and alternates before flight, and use them almost as a reminder, and a crib-sheet for the vital headings and altitudes (a bit like a plog) in flight - I'm a very new IMC pilot, so I don't know if more experienced pilots do the same. None of these tasks takes my attention away from looking out and flying for nearly as long as using a whiz-wheel.
The one task which many people do in-flight, which does take your attention away from more important matters, which you don't mention, is studying a chart (or a GPS). I suspect very few of us would be able to honestly claim that we have never had our head stuck in a chart for too long, only to look up and see something we'd have liked to have seen earlier. And I would think that using a whiz-wheel is more demanding than studying a chart.
FFF
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