I find it awkward to choke down on my clubs which I know is my issue. I was having trouble with consistency with my irons and my pro determined my clubs were too long for me. So I worked on choking down on my clubs and my consistency and contact significantly improved. I got new shorter irons and the difference was amazing.
I completely agree about making sure you are fitted with the proper length or making sure to choke down on the club if the clubs are a bit long or if you are lacking good contact.