Of course you can force stop programs within the system itself. I see that arguement being the same as someone asking why you would run an app such as pure grid calendar. I mean the droid comes with a calendar app built in right? What is the harm in having an app that does the same thing but has a far more user friendly layout. Sometimes it just seems like people are arguing about stuff for the sake of arguing.
I agree that having a task killer and using it to close EVERYTHING every 15 minutes is retarded and will slow down the system. Use it wisely and it will come in handy.
Simply because it is 100% not necessary. A better calendar app may be necessary, beacuse it may offer more features or may look better than the stock. An android (linux kernel) OS simply does not need nor benefit from a task killer. I think everyone is in an MS mindset, and that's why they feel its necessary.
Linux handles memory far more efficiently than Windows. Windows leaves too much memory that should be cached, free, and caches at stupid times. It's all about hardware/software interaction. Linux uses memory like its suppose to use memory. All available memory (pretty much) is used for programs and caching. Swapping is only used when absolutely necessary unlike windows that'll try to access swap anytime it wants. You DON'T need a task killer because it's overkill in an android (linux) system. The reason it could be harmful is because it's an app created by a third party that may be unstable. I think any benefit achieved by a task killing app would be negligible but don't quote me on that.