Such a theory would be perfectly true, if it had any basis in facts. The plain answer is, that later scribes easily might have eked out lines which seemed deficient; only, as a matter of fact, they did not do so. The notion that Chaucer's lines run smoothly, and can be scanned, is quite a modern notion, largely due to Tyrwhitt's common sense. The editors of the sixteenth century did not know that Chaucer's lines ran smoothly, and did not often attempt to mend them, but generally gave them up as hopeless; and we ought to be much obliged to them for doing so. Whenever they actually make amendments here and there, the patching is usually plain enough. The fact is, however, that they commonly let the texts alone; so that if they followed a good MS., the lines will frequently scan, not by their help, but as it were in spite of them.
[§ 17]. Let us look for a moment, at the very edition by Stowe (in 1561), which contains the earliest copy of The Court of Love. The 9th line of the tales runs thus:—'And smale fowles maken melodie,' which is sufficiently correct. We can scan it now in the present century, but it is strongly to be suspected that Stowe could not, and did not care to try. For this is how he presents some of the lines.
Redie to go in my pilgrimage; A. 21.
For him, wenden or wende was a monosyllable; and go would do just as well.
The chambres and stables weren wyde; A. 28.
He omits the before stables; it did not matter to him. So that,
instead of filling up an imperfect line, as Prof. Morley says he would be sure to do, he leaves a gap.
To tel you al the condicion; A. 38.
Tel should be tel-le. As it is, the line halts. But where is the filling up by the help of some convenient monosyllable?
I add a few more examples, from Stowe, without comment.