I read some books about typography and design. They all recommended to avoid lines in tables, and instead to make use of spacing. I found that reasonable and adhered henceforth to those rules.
Recently I ran into discussions with spreadsheet users, who doubted these rules and argued that grid-lines are better since all programs have them turned on by default.
I also read an article that explained the problem with lines: the human eye first has to remove them before it can focus on the content of the table. If somebody would know this one or similar scientific findings about perception of data, I would be glad as well.
Is it in fact better to avoid lines? Why? Do you have any references you could provide to back this up with?