edge connector rarity [was Re: HP9836C colour alignment (grey scale tracking)]

[Chuck Guzis]

It should probably be mentioned that there are edge connectors and 
then there are edge connectors.  The cheap ones use a simple leaf 
contact that can gradually lose some of its "springiness".  The 
better ones use a more complex contact that retain their strength 
much longer and have multiple contact points.  See, for example HP US 
patent 6152790.

You get what you pay for--unfortunately for all of us, edge 
connectors were a common area of cost-cutting.

Cheers,
Chuck