I changed it to...
fields = Object.keys(Blaze.TemplateInstance.prototype)
blazeComponentMethods = Object.keys(BlazeComponent.prototype)
for i in [0...fields.length]
methodName = fields[i]
if methodName in blazeComponentMethods
continue
method = Blaze.TemplateInstance.prototype[methodName]
do (methodName, method) ->
...
But it seems like there's some other uses of that loop in there... not sure if that will be enough for all cases...