If you read posts/blogs to learn and equip yourself to loose weight and improve your health, there is more helpful information in a long messages/article, although there can be helpful small tid-bits in short messages!
If you are simply jumping into a blog to grab and go to play the Spark Point game! Any size blog can work because reading the blog isn't required to get points! Just post a simple all purpose response like emoticon .
If you are in a hurry because you have so much on your agenda, It might be helpful to prioritize what is important! Maybe reading a long informative message really isn't worth your effort!
You are in control and what you get out of something is equal to what you put into it!
Your challenge is to try both and determine which actually provides you with a greater benefit!
Good luck and best wishes!