I always thought my flimsy tripod was fine for catching planets from my deck. After a gust shook my scope and ruined a Jupiter shot, I see why a heavy base helps. In my experience, a stable mount can turn a fuzzy blob into a clear photo, but your mileage may vary.
True, my shaky hands prove that point every time I try to take a photo. I'll pick a stable, clear shot over a fancy, blurry mess any day. Guess I value planetary stability in my pictures, too.