Arkady, as always you are absolutely correct. When the OJTI leglislation was passed some 3 years or more ago, the 2 years valid on position as not included. The only criteria was that you must have held the rating, and by implication, have been valid for one year. It was agreed at LATCC and followed by LACC that we would still keep to the two years experience before anyone became a practising OJTI. However it was stated that in exceptional circumstances, such as someone showing exceptional ability we could reduce to one year. However there was no reason why anyone could not do the course provided that they were not attested until the two years were up.
For what it's worth I think that some people will make very good OJTI's after one year, whereas others are not suitable after 40 years!!