Mm, don’t know if that’s all that possible - this is a 19mm strap in 19mm lugs. But I think the Omega spring bars have the ridges quite far in for some reason, seems I always have to pull them quite far out with the spring bar tool when I change straps and that squashes the leather a bit.
I know, it's much better to have the correct width. I'm just hoping some of the straps are a bit ''fatter'' than the width indicates. For example, some leather straps that I put on the BB58 needed quite a bit of squeezing before they fit in. We shall see.
Let me know if you find a good way. I intend to “massage” my 20mm straps into the 21mm lugs in the Longines.