I'm struggling to understand why you need comment scores to know what to think about something. I can make up my mind about a comment's quality using the info available to me right now.
Let's take the oft-repeated example in other comments: two comments on MySQL, one with a handful of points and the other with a lot of points. There are a number of indicators of comment quality:
>> comment sorting works very well
>> if a low-vote comment is controversial, you will surely find spirited discussion below it--the volume of discussion would be an indicator of community disagreement
>> hit up Stack Overflow and find out if MySQL works as stated in the low-vote comment or if it works like the high-vote comment describes.
The arguments for visible points boil down to "I don't know how to think about this statement, so I need external confirmation." Indicators of comment quality still exist, and karma gamesmanship looks like it has decreased a lot. Finally, you really want to avoid groupthink--hiding scores accomplishes that pretty well.
Let's take the oft-repeated example in other comments: two comments on MySQL, one with a handful of points and the other with a lot of points. There are a number of indicators of comment quality:
>> comment sorting works very well
>> if a low-vote comment is controversial, you will surely find spirited discussion below it--the volume of discussion would be an indicator of community disagreement
>> hit up Stack Overflow and find out if MySQL works as stated in the low-vote comment or if it works like the high-vote comment describes.
The arguments for visible points boil down to "I don't know how to think about this statement, so I need external confirmation." Indicators of comment quality still exist, and karma gamesmanship looks like it has decreased a lot. Finally, you really want to avoid groupthink--hiding scores accomplishes that pretty well.