look at Blackie go!
I do have to give you some noodles, even though you know your cat and Blackie always bounced (and he did), nobody should be shooting a 34. If this was the one time he didn't bounce, you could have been in big, big trouble so next time he tests in the 30's at shot time, please stall until he's at least 50. (end public service announcement....) ;-)
In my opinion, the 34 is probably coming off some shed action from the old 5 unit dose. I do think the fact that he cleared that bounce so quickly means that another reduction could be right around the corner. You really can go either way, if you're able to get some extra spot checks tonight and tomorrow to keep Blackie safe, you could try holding the 4.75 and see if he shows another low number. If you can't do the extra spot checks, you can go ahead and reduce to 4.5. More than likely it will work (and if it doesn't, then we go back up, no big deal). What do you think?