Will I Repeat Myself On The Dimi?

Recently, a harmonica playing musician that I respect brought up an interesting question on a harmonica forum about playing the Dimi layout chromatic harmonica.

His question is a perennial one for those who are considering trying the Dimi.

Most of us know by now that, due to the symmetrical construction of the Diminished scale, the Dimi only has three unique fingering patterns across all 12 keys. In other words, the key of Bb plays exactly the same, in terms of its "fingerings" as the key of Db, the key of E and the key of G. For example, a Bb Major scale will have the same exact fingering options as the keys of Db, E, and G do.

The harmonica can be a tough instrument, and while we might ideally be musically pure and transcend our instrument, at a certain point we will have to work with the practicalities of the harmonica and find what works on it. If our instrument has only three unique patterns, and the other nine keys are repeats in terms of fingerings and other physical characteristics, isn’t it likely that we will repeat ourselves more often than we would on a traditional harmonica?

A common, and understandable, argument for the traditional Solo layout goes as follows: Personally I like the fact that the "fingerings" are different for each key. It gives each key its own character. It is less boring for the listener. In other words, the Solo layout chromatic, which is the traditional chromatic harmonica that 99.9% of chromatic players play, has a unique fingering pattern for each key. This fact somewhat "forces" an improvising musician who plays the Solo layout to play different phrases in one key that in any of the others. By the way, let me assert that I am never arguing against the Solo layout chromatic harmonica. Too much great music has been on it. Toots Thielemans is one of my favorites. I am simply comparing the Dimi and the Solo layouts.

Here is the response I gave:

This is an interesting question.

Will an improvising Dimi player tend to repeat himself more often (than a Solo player would) because of the repeating patterns on the Dimi layout? It would be a logical conclusion, but I'm not so sure.

In other words, on the Dimi, all fingerings for the key of G = key of Bb = key of Db = key of E.

We know that the Solo player won't play the same patterns in E that he does in Bb. But will the Dimi player tend to play similar patterns in E as to what he plays in Bb?

Let's take, as an example, playing Major scales in stepwise fashion. This is a very limited example, but it might illustrate something.

So, to summarize, on our selection of scales that go from E major to Bb Major:

And, if we were to limit the Solo layout to a less generous interpretation, due to somewhat redundant enharmonics:

Which of these scenarios is more advantageous? Which gives a richer set of options? Which player has more variety to work with? I think Dimi is very competitive, and offers a number of other advantages as well.

Of course, this is an imperfect example. There are keys on the Dimi that have less options. (There are only four options for some keys). But I think it illustrates that the obvious surface assumptions may not be that reliable.

P.S. This doesn't even get into half valving, which is an option for additional enharmonics on the Dimi.