Impy - sounds like the one i went through - i too have that issue of appearing ok and shiny on the outside. hated all those stupid "list back the 5 words i say" thing and math questions. i didn't get it thru him. he said see a medical doc. the med doc said i clearly had psych issues. wished they'd have gotten together. but i appealed it and got it.
sadly, sometimes it is just luck of the draw (now that I am thru, i know someone working for an ssdi attorney) - in some cases someone will walk in, tell the workers to randomly pick 12 files - then of those 12, the guy picks six from each worker and passes them without even looking at them, then say deny the rest (again without looking at them). i wish i were making this up - i felt enraged about it.
Keeping the faith for you impy! keep going with it, no matter what. get a good advocate - i did, and it made all the difference.