Maybe I am shallow, and it says a lot about my attitude to art, but now I am going off the painting I bought last year. If I like the painting, I should like it whether it was painted in a Chinese factory, by a struggling artist in Dublin or by Jack B Yeats for that matter.
Brendan - As you know I'm a sculptor (though working at the moment as an NHS psychotherapist) and most of my friends are painters or involved with theatre. That 'going off' phenomenon is perhaps not so much linked with these pictures now being part of a deception but rather that they (not you!) are 'shallow'. Significant art works on the viewer slowly and opens up new thoughts and feelings over time. The Boddhisatva Buddha, a large stone carving in the British Museum, gave me weekly food for thought during my four years art training; I spent a couple of hours a week sitting looking at the Rothko tryptich in the Tate Gallery. I still haven't finished with them!
There is a lot of garbage talked about art and its 'value' by pedants and peddlars. The best approach for anyone wishing to develop a relationship with fine art is to start visiting galleries on a regular basis (and Dublin is blessed with some wonderful public galleries and collections, like the Lane Bequest), spending time absorbing and feeling and developing a personal taste. Then, if they wish to 'own' art themselves attend auctions or visit the Degree Exhibitions when many contemporary artists put works up for sale. The only rule is 'follow your heart' but that doesn't mean you won't have a 'change of heart' and lose interest in a picture.