
Our 1N is semiforcing. Our 2D is GF with 5 diamonds.
We tend to find ourselves using the relay whenever possible, so if we have Axx xx KQxxx AKx we are likely to bid 2C and not 2D.
This means that 2D is underutilized. We usually only bid 2D when we don't have those three clubs (again, the GCC)
Thinking that 1M-2D can show a good 11 to bad 13 with 2-cd support for the major. When playing GCC we also have to have 3 diamonds

Of course, really 1M-2D would be a 2-way bid showing this hand type or the rare hand types with 5+ diamonds and lacking 3 clubs.
1M-2D, 2M would reject game opposite the 2-cd LR. Otherwise, we're in a GF.
I think Chris does something very like this, but his 2D has to handle the GF diamond hands as well. Ours will be less frequent as we prefer to respond 2C.
That's a good thing, too, because of the awkwardness created when 2D does not initiate a GF.
What would a 1N response be? Either less than GI or GI with shortness in the major or lacking that third diamond.
What are the downsides? Sometimes we would have discovered a superior minor suit fit and have to play 2M. Again, the 1M-2D with GF diamond hands are more awkward.
The upsides? Getting to play 2M instead of 2N. Decreasing the frequency of lost 13 opposite 12 hands (say partner is 5332 13 and passes 1N)
When we're playing Midchart, we can use 1M-2D as the LR with 2 and forget about the diamond requirement and forget about the GF with diamonds.