A Query On Licetness

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Browsing Denzinger, as you do, to try to find a clue to just what it was that the Council of Florence said in 1215 which impelled the Friars to start encouraging lay use of the Little Hours as a devotional aid, I stumbled across the letter Perniciosus valde which Pope Honorius III wrote to Archbishop Olof of Uppsala on 13 December 1220 adjuring him to use a lot more wine than water during the admixture at the Offertory.

It reminded me to ask if anybody else has noticed a practice of some permanent deacons of only adding water to the wine in the chalice being used by the priest and not to those being offered to the laity?  I've noticed two do this now in two different parishes in two different dioceses.  I can't work out what point is being made, unless it is a subtle protest against the use of multiple chalices instead on one single chalice large enough for all the wine which is to be consecrated.

It's very easy simply not to queue up for the chalice and to return to your seat after receiving Communion, and I'm sure that the wine in the chalices without added water is as consecrated as that in the priest's chalice, but does anybody know if there is a specific instruction for this circumstance either way, or whether there is an "English practice", or whether I have simply stumbled upon the same creativity twice.
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