Alloy databinding fetch additional data causes strange behaviour in scrollview

When fetching additional data in a scrollview ala infinite scroll using fetch I get a strange result, the scrollview empties and fills several times before populating with all the views after a fetch.

<ScrollView id="content" dataCollection="properties">
    <Require src="property.row" />
</ScrollView>

<View id="row" class="row" className="property">
    <ImageView id="image" />
</View>

Using methods to detect the bottom of the scrollview I then try:

properties.fetch({
    query: lastQuery + ' OFFSET '+ thelength,
    add: true,
    success: function (col) {
        (col.models.length === thelength) ? Ti.API.info("done") : Ti.API.info("success");
    },
    error: Ti.API.info("error")
});

I have put in checks to prevent multiple fetches but nothing seems to work, I still get the above strange behaviour.

video displaying what I am seeing.