Yes, you are right Luckyboy and it is something which I take notice of, especially if one of the top hoops is replacing a perceived "less fashionable " jockey. For instance,today, there is an example:
MR5 No1 Glefti
top jockey, S. King, replaces apprentice, Michelle Payne-expect a good run.
Other potential winners today are:
Gosford R3 No2 Don't Tell Me Lies* scratched from Sydney to run here.
Adelaide R2 No12 Entice*reasonable run last start and drops back in class, from the strong McEvoy stable and ridden by top jockey, S Price.
Good Luck.

Cheers.