For so many reasons. Let's review.
It has the ability to turn my big, strong, thoughtful husband into an irritating, gets-in-my-way, can't-do-anything-right-no-matter-how-hard-he-tries lump on my sofa.
Estrogen transforms Bug from a lovable, let-me-spend-all-my-free-time-with-you, here-let-me-hug-you kid into a loud, whiny, never-happy-with-anything, always-wants-to-be-somewhere-else, messy little creature.
Estrogen has gotten wilier (more wily?) with Jock. With this child, Estrogen has begun a multi-faceted attack. On the one hand, it has created an always argumentative Attitude Monster of Epic Proportions, a creature that is no longer able to respond politely to the gentlest of inquiries into his life. The other attack is sneakier. It has crept up and begun waging a battle at my most vulnerable points. Estrogen has gathered new recruits. And these new recruits have the ability to make my teenage son shower daily. Wear deodorant. Wear cologne (And Lord help us..... there is no sense of moderation with this particular side effect.). He now spends a larger amount of time making sure he looks perfect before he even leaves the house. Worse.... Estrogen has stationed these new recruits at various sniper positions along the path of his teenage-hood.
This is a potential problem. Its been my experience that while occasionally Estrogen enjoys hanging out as a group, at its most basic it does not like to share attention. It especially does not like sharing the attention of Testosterone with other pockets of Estrogen. So you can see how Jock is going to have a rather difficult situation on his hands: Balancing the Estrogen he his familiar with against the Estrogen he wants to bring into his world.
Although I have a sneaking suspicion that Estrogen is at its worst with me. I completely turn from a rational, loving, patient mother and wife into some horrific energy and emotion sucking beast. A beast who when looking upon someone that I adore, sees only their absolute worst qualities (reference the above statements about my darling family. You'll recall that none of them are actually able to have Estrogen moments, therefore the statements are completely my observances of them). A beast who leaks a copious amount of water from her eyes (seriously.... an entire box of tissue?? damn it!). A beast who has no ability, or desire for that matter, to regulate her chocolate and caffeine intake. And I seem to be unable to defend myself against this beast. Unlike men.
See, the men/boys have a tool in their arsenal to fight against the effects of Estrogen. They have come equipped from birth with Testosterone. Which, while amazingly combustible and unstable, has a unique ability to counter-act the effects of Estrogen. Sadly, only males of the species seem to have this tool.
But, to quote Dennis Miller:
That's just my opinion. I could be wrong.