I've noticed that Reform and Conservative often use small "scarf" talleisim (here's an image). Where did this practice originate? (Is there any connection to the scarves that some Christian priests wear, and if so, could there be an issue of chukas hagoyim)? Is there some ideological reason why Reform and Conservative continue using "scarf" talleisim b'davka, or is it just something that they are used to doing for historical reasons?
from what I have heard the original reform movement made change in in davening both the liturgy and the dress of those leading to be more like the church. This was part of their goal to become assimilated and then so they thought become more accepted by non-Jews. Today I don't think this people today use this tallis for this reason but rather after several generations it simply became popular. The main problems with such tallesim... 1)they often aren't big enough to require tzitzis. 2)even if they are large enough wearing them in such a manner is problematic as each of the tzitzis are to be on the four corners around one's body and not all in the front.