[d5tryr]

First of all it provides a visual cue as to the rate at which a podcast is being played at, a constant cue rather than an indicator that has to be found and read. For that reason, on a purely practical level it is useful.

More importantly though you seem to be suggesting that an interface should never make reference to the technologies that preceded it, for fear that a teenager might be made aware of something they've never seen before?

What a terrible thought, that someone might be encouraged to investigate analog audio technology. Why can't an interface be a history lesson too?

[d5tryr]

I just noticed that the spool sizes are also accurate indicators of duration. The two spools, how long you've listened for & how long remaining are another elegant way of visualising duration. Sometimes you are interested in time listened and sometimes time remaining, this provides a visual cue for both.

Smart, and again more expressive than a label.