The other thing about the "eye test" is that hardly anyone watches other games, besides the Sox, and nobody watched every play of every MLB game, so it's hard to know comparative value of anyone without stats or metrics to help with personal observations.
Stats can be deceiving.
Stats can be cherry-picked to suit your purposes.
Stats can miss the big picture or another aspect of player value or non value.
Stats don't lie, though.
It always gets me when an eye test guy says something like, "so-and-so has been in an awful slump, lately," and you show some stats that show the guy has a .900 OPS over the last week, and .850 over the last 2 weeks, and an .800 over the last month, and they still stick to their beliefs.
Sure, some of those hits, in that time period, might have been lame, of the players has made outs every key situation during that time, but facts are facts.