Shirt pocket carry!
You should of said that earlier. A few months ago I worked first shift and had to wear a monkeysuit in the art galleries (security). One of my companions was a new knife I'd bought--small, light and very slender. I had bought it because it was so cute, and had a sweet looking black Ti blade coating. It fit in my shirt pocket like it wasn't even there, and accessability was perhaps easier than anything I could keep in my pants pockets. It was PERFECT for opening food packets and such.
And you may not like this:
It was a Benchmade Ascent Model 824! I'm one of the few folks who like Ascents, apparently, and I used to carry my large one (older with the round hole) every day.
Like I said, this smallest of Ascents is very light and slim and fits shirt pockets perfectly. There are two drawbacks, however.
One, it is not as easy to manipulate as larger, wider knives. Part of this is inherent in it's slenderness. The other part is due to it's oval hole with bevelled edges. You just can't get a purchase with your thumb as easily as a sharper edged hole. It's a quarter inch longer (opened) than my Standard, yet the Standard is much easier to manipulate.
Two, it isn't a Spydie!
If you check out my posts around here, you'll see I'm a dedicated Spyderknut, and if I knew of any Spydies which I thought would make better shirt pocket knives, I'd name them. If by chance you are wearing heavier cloth, like coveralls, one of the heavier Spydies would work well, no doubt. But if I went back to carrying a shirt pocket knife in an average weight dress shirt, it'd be this little cutie Ascent! One of the few times I'd recommend something other than a Spyderco, especially here in the Spyderco forum!
Perhaps a Cricket or a Meerkat may work for you? I don't have either one yet, but they are both tip down and should be easier to open than the Ascent. They just aren't as slender.
Karl