These are great, and I may be using the Alleluia for the third Sunday.

I have a request, however, from those who compose such settings. Only rarely are settings written for common psalms, responses, and alleluias as listed in the lectionary (cf. http://catholic-resources.org/Lectionary/1998USL-Psalms-Alleluias.htm). By Flowing Waters is terrific (and what I will be using for the the resp. psalm), but it reflects the Simple Gradual, which is not infrequently different from the lectionary's seasonal choices, and which I sometimes like more than the Simple Gradual's choices.

mrcopper, your comment appears to be contrasting an apple and an orange. The Simple Gradual contains simplified proper chants for various feasts and seasons of the liturgical year. Most "sets" include a responsorial psalm or an alleluia psalm.

The Lectionary for Mass has a proper responsorial psalm included in every set of readings for Mass. There are also a couple dozen "seasonal responsorial psalms" which, at times, may be substituted for a proper responsorial psalm.

So the comparison should be between responsorial psalms in the Simple Gradual and responsorial psalms (both proper and seasonal) in the Lectionary for Mass.

My anecdotal experience is that when the revised Lectionary for Mass was introduced in the spring of 1970 the seasonal responsorial psalms therein were used quite often in the following decade or so. Several composers even composed collections of these seasonal responsorial psalms.

Over the past 20 + years the proper responsorial psalm has come to be used fairly exclusively. There is still some use of the seasonal responsorial psalms, but not much.

I think that the responsorial psalms in the Simple Gradual have rarely been used in place of responsorial psalms in the Lectionary for Mass. One is more likely to hear the introit or communion chants from that collection, than the responsorial psalm.

Once again, these are my general impressions. I don't think any kind of statistically verified data exists for this question.