Hi Wendy.
I have seen and heard this going on for years. I can see both sides of it and although a cat can get held back by these others who keep entering the Opens, I am a great believer in saying 'even the best can be beaten' and if a cat is good enough to get the title, he/she will get it regardless of others who are entered. Sometimes it is a case of finding a judge who particularly likes your cat, or of getting it just right and your cat being in tip-top condition when the other 'Top' cat maybe is out of coat?
It is a competition after all, and rightly or wrongly in some people's eyes, those 'top' titled cats are entitled to be there too.
JMHO.