Normally a slight deterioration of eyesight would not present a major problem indeed, but one has to bear in mind that it is not the ATC Provider, airline or flying club who is deciding whether or not it is acceptable.

The medical certificate of the appropriate class is issued by or on behalf of the CAA unit responsible for safety regulation. The past spending of any money on a candidate’s training is not very relevant in this respect.

Of course it is not advisable for a candidate, who only just meets the medical requirements, to start initial training for a professional career, risking not to meet the requirements for re-certification later in the career.