I don't think this is legal
When you play favorites, you drive racers away. When tracks close due to lack of attendance and participants, one wonders whether those owners ever consider that it might be their own damned fault. Have you ever noticed the "teacher's pets" seem to be the most unlikable people at the facility?
If you have a rule book, it applies to everyone. The only time I would agree with an exception is if the person in the other lane agrees to it. Many times that person will extend the courtesy because they came to race and maybe hope "do unto others" still counts for something. In that case, that sportsman should have the final call of "enough is enough" to disqualify his would-be competitor. Otherwise it's, "Sorry, but them's the rules." Lack of preparation on your part does not constitute an emergency on mine.