Define "checks and balances"

I need to get irate for a second. If I hear one more supposedly smart person use the term "checks and balances" in reference to the political parties, SOMEONE is going to get punched in the nose. (Figuratively speaking.)

To sum up, the "checks and balances" that are the basis of our governmental structure have NOTHING to do with political parties. Got that? NOTHING.

The parties are NOT meant to check and balance each other. Comprende?

Example: here's a gem today from Bill Kristol on the Washington post website, discussing the Specter defection:

[Obama will] be responsible for everything. GOP obstructionism will go away as an issue, and Democratic defections will become the constant worry and story line. This will make it easier for GOP candidates in 2010 to ask to be elected to help restore some checks and balance in Washington...

No wonder the guy got fired from the NY Times. If you willfully convolute our Constitutional government with party politics, you deserve to be hamstrung.

I feel like I'm talking to a 6 year old to say it, but do we all agree that the American system of "checks and balances" refers to the three branches of government - the Legislative, the Executive, and the Judicial - which each have powers that "balance" the others and keep them in "check"?

Jesus, people. Its like 5th grade civics. Pick up your kid's textbook.