Excuse my butting in, but your statement "
went to the last stand for a '93'" says quite a bit. I dont look at my card all the way round and quite honestly havent a clue how many I need on the last stand for a X score.
Admittedly its a lot easier not to count your misses and keep a mental check of your score when you average mid 60's but if you can just walk up to a stand wether its the 2nd or last and forget all that has gone before good or bad and not have the mindset of "I need X amount for a X score" you will let your obvious talent do the work instead of your head screwing up the hard work.
Maybe worth having a chat with Phil "The Witch-doctor" Coley, helped me a lot
Your technique is obviously sound to be getting a shot of 90+ scores so I would suggest its a mental approach that will get you the extra few birds to get you over the line