as has already been mentioned, Suzuki had them on their triple range (GT380/550/750) in the seventies, built into the dash.
If they were really needed then why not have them on cars?
Regretably ... I have to say my current car does indeed have one set in the intrument display.
When you take it out of auto the lever works as a push fwd to change up a gear, pull back to change down a gear and the ickle display tells you which gear is active.
I'm certainly not against them - nor am I slagging off those who like them .. I just feel personally that it's more important to be able to feel/tell which gear your'e in.
If you really must look at something what's wrong with the rev counter & speedo.
:dunno:
If a quick glance at that still leaves you unsure then ..............
and that's why I wondered if it was low miles folks (on the 'bird) who found it difficult to tell simply because they hadn't yet got the feel for the relationship between revs vs speed.
Not having a go, just my simple brain struggling to understand :-0)
ps .. I did appreciate it on the GT380 at first .. but after a couple months I was used to the bike and didn't need to look at it......