If you have never appreciated the job playtesters do for you then wait till you give them a brilliant bit text you have written and watch them break it.
My playtesters for Ghosts of Albion were some of the best. In my own group I was arrogant enough to think I had the Cinematic Unisystem game wired so tight nothing could happen. So I tried out a few new things. One of which was an updated combat system and another was an alternate magic system.
Well no sooner than when the words "break it" came out of my mouth did my players do exactly that. Rather gleefully too I might add.
The combat system was just slow and had too much rolling.
The magic system, that I loved, didn't work at all. It was in fact a complete bust.
So the magic system in GoA now was born out of those ashes. But it goes to show you that what looks and reads great on paper doesn't always play great on the table.
And it never really changes.
Just recently I worked out a new magical combat system for my Basic-era book "The Witch".
I thought it was great. So I tried it out. It was not as great as I hoped. Not bad mind you, but nothing like the one in GoA.
So I tweaked it, and polished it and tweaked, and tweaked. And sooner or later I ended up with a system that was more complex than anything else in the game which was the opposite of my design philosophy.
At present the magic combat system of Wizard vs. Wizard (or Witch vs. Witch, or Witch vs. Wizard) is on hold.
The trouble is now The Witch is off to the proofreaders (sans magical combat system) and I am still at a loss on how to do it so it works well and works fast.
Back to the drawing board I guess.