If indeed there is a biological source for this condition, then this sort of therapy would border on witchcraft. Yes there are always children who exhibit gender variance and then outgrow it but what about the ones who are clearly transsexual and in need of a different type of assistance?
It's a fine line to walk because we could fall prey to putting kids on androgen blockers too early and set them on a path that could lead to personal disaster. On the other hand employing exorcism-like practices based on the belief that God does not allow for mutations of gender identity smells an awful lot like the 15th century.
There is likely a careful middle ground here and it needs to be tread very carefully. Growing up in silence as I did is definitely not the right way; that much I know. But with an ethical and unbiased approach I believe it is possible to treat a child without undue leading and badgering.
Andrea James covers this topic very well in her recent article and it is well worth the read