impression proofing

[dls]

you could make the tollerences between the keway and the key so tight and have a key which is so fine that removing metal to loosen it up in the keway would cause it to break in the lock.
you could cut the middle out of a bottom pin and insert a rubber or a spring so that in normal use it works ok and during impressioning it acts like a shock absorber preventing the impressioner from getting an accurate or reliable mark by reducing the pressure between the bit and pin.
another thing that could be done is to use a side bar or pair if bearings which requires a hole to be cut right through the key near the bow weakening it considerably the bearings would lock into a pair of holes or dimples in the body if there was no hole in the bit and would give some level of drill protection.

[vov35]

... Capitalization please.

1) perfect tolerances would defeat every form of manipulation. This doesn't exist
2)Imagine the wear on these pins with time?
3) What if somebody uses a wrong key or has a sticky lock, and snaps their key?

[dls]

SORRY ABOUt the caps thing shift buttons acting up baby sick

tight tolerance is not realy a problem with the plug and the body just look at the best cores i have some that are 30 years old and like new although the pins are worn flat

as for wear on pins i am normaly thinking of high security apps when i consider my ideas cashrooms etc typically 2 users opened about 10 times a week

as for the wrong key that could be a bumpkey a blank for impressioning or a pick. normally ease of access and user friendly features like allowing you to try lots of different keys create weakness, a delaying factor built into a lock would improve security no end