“The nature of any particular necessary connection depends on its context, for example electrical, familial, physical or logical. The 20 relevant context in this case is the scheme for charging and recovering VAT in the member states of the EU. The process of off-setting inputs against outputs in a particular period and accounting for the difference to the relevant revenue authority can connect two or more transactions or chains of transaction in which there is one common party whether or 25 not the commodity sold is the same. If there is a connection in that sense it matters not which transaction or chain came first. Such a connection is entirely consistent with the dicta in Optigen and Kittel because such connection does not alter the nature of the individual transactions. Nor does it offend against any principle of legal certainty, 30 fiscal neutrality, proportionality or freedom of movement because, by itself, it has no effect.”