Funny as that is basically Ronnie Coleman's (Mr. Olympia) big saying:
Yeah just not worth it to lift so heavy that I hurt myself and then end up taking more time off. Now I just go in to stay in shape and have stopped trying to get huge; plus realized it really isn't that healthy to be a giant bodybuilder (like Ronnie above...guarantee that guy could not run a few miles to save his life). The good thing is I've kept most my stregnth even though I'm leaner.
Nice, I like that workout! Best success I have seen is with programs that constantly keep your muscles from getting used to a workout; hence the different weight and reps in the program. I like how it encourages to keep pushing yourself (increase weight by 10%). Continue doing this and you will be amazed how much you will be able to lift compared to when you started. MY bench press was horrible when I started but I forced myself to keep adding weight even though I hated it and amazed now at the difference.