I appreciate your comments on this issue. I was aware there is more than one type of RMV. I did not know one could make an educated guess from inspection which of the rose mosaic viruses is infecting the plant, and I appreciate you pointing that out to me.
Whatever limited research there is on the effect on plant growth in home gardens, I can say anecdotally that the virus infecting my Spectra has a very significant effect on growth and flower production. This plant in its early days when there was no sign of virus would grow up to 8' tall or so, and had lots of flowers, but as the years have worn on and the leaves have shown more symptoms, it does not grow as tall, and now has few flowers.
Q