Only keeping track on wins and losses in baseball doesn't accuratly reflect a record.
for example look at todays games...
If you go 1-1 and the win is the WSox...then you'll break even on the day.
If you go 1-1 and the win is the M's...then you'll lose $25 on the day (assuming you bet $100 a unit on each game).
The total units on the year are more important than the actual record. You could be hitting 65% in baseball but still be down money if you're regularly betting favs. And vice versa...you could be hitting 45% and be up money if you're betting lots of dogs.
Just my $.02 on the situation.