Have you seen Darlington's 1912 thoughts? 100 plants along a carriage drive?
"from BEDDING ROSES by H.R. Darlington

GRUSS AN TEPLITZ, H.T. (Geschwind, 1897)
This Rose has good and attractive foliage and a strong semi-climbing habit, growing readily into a good symmetrical, rather upright bush. It is not my ideal of a good habit for a bedding Rose. The flowers, which are produced in loose clusters, are semi-double and not well shaped, but very brilliant in the garden. The colour is normally a bright crimson, occasionally tending towards maroon. They are not well carried, and much inclined to hang their heads. They are produced in considerable quantity and very continuously, the autumn crop being specially good. The flowers are fragrant and the plants have a magnificent constitution. They are scarcely at all affected by mildew but if there is any black spot about they generally get it.
This is another Rose which I should not think of using for bedding myself, and I notice that several of my friends think it too tall for that purpose. Many, however, call it a good bedding Rose, and those who do, generally recommend that it be pegged down. Mr Page-Roberts and Mr Easlea, however, advise occasional lifting to check its growth, and the latter suggests growing it in poor soil. I have no personal experience of this Rose as a bedder, but think it should be used in a large bed to produce an effect at a distance, and that the Rose will be found at its best when grown as a large bush or as a standard. I fancy that to get the best results it should not be pruned hard, but treated rather like a Noisette Rose, encouraging young growth, keeping this rather long and cutting out as much old wood as can be spared. I have tried the starvation method, but in this garden it has not proved a success. I have seen this Rose in Lancashire, not many miles from the sea, growing as comparatively low bushes and flowering well, so possibly in the north it may be more worth trying as a bedder than in the south.
For those who wish a bed of Roses something after this colour I should myself be more inclined to recommend either Petrus Donzel, very like a dwarfer Gruss an Teplitz, or better still, Charlotte Klemm. They are both China Roses, and I should not be surprised to hear that Gruss an Teplitz had China blood in it. I have never heard of its parentage. The strong points of Gruss an Teplitz are its brilliant colour and strong constitution, perhaps also its attractive foliage. Its weakness as a bedder lies in its strong growth, dislike of close pruning, and the want of form in the flowers. The position in which Gruss an Teplitz would be most likely to prove a satisfactory bedder would be in a large bed, to hold say 100 plants, along a carriage drive, outside the garden properly so called; and I call to mind a brilliant bed of something this size which I have occasionally seen in a nursery garden when travelling by train, and have put down in my own mind as a bed of Gruss an Teplitz, but I have no personal experience of beds of this size in the garden. "