Well, there are obviously limits. A badminton racquet would fail structurally the first time I hit a tennis ball with it. It's not within the realm of reasonable for tennis play.
When considering extremely light *tennis* racquets against heavy pace, they will
only work if you can swing them fast enough. So if you can't swing very fast,
you definitely need a heavier frame.
...
So the amount of weight you need in your frame to handle heavy pace is variable for every player. I would say a general rule, assuming your preparation is up to the task, is that you can handle as much pace as you can hit. So if your current racquet set up allows you to blast 80mph forehands then you should be fine handling an 80mph forehand. If someone comes along with a 90mph forehand, then you might be in trouble. Of course if you can hit an 80mph with good control, then your opponent is probably going to have his work cut out for him anyway, especially if you don't hit to his forehand.
I tend to agree with you, but even people that swing very fast and can happily use a lighter frame, they still face a big problem: more shock and harm to their elbow and shoulder.
More from rr.com:
"If you are inclined to buy a granny stick, consider this: if you were in a car accident, which would you rather be driving, a compact or a truck? We all know that the light car will get crushed. The collision of a racquet and a ball is the same thing: a heavy racquet will keep going on impact, crushing the ball more for better pace and spin.
Light racquet partisans argue that because
you can swing the light racquet faster, it will hit harder than a heavy racquet. Granted that if you have the time and energy to execute a long violent stroke, you can swing the light racquet faster and get greater head velocity on impact. Three problems with that: (1) a violent stroke is harder to control; (2) when you are stretching for a shot, you don't have time to execute a long stroke, so velocity will be small and because racquet weight is small also, your shot will be weak; and (3)
the light, fast racquet will slow down a lot on impact, stressing the arm.
All of that lost energy will have to go somewhere, like your arm. Momentum (mass times velocity) and not force (mass times acceleration) or energy (1/2 mass times velocity squared) is what counts in a collision. Oops, sorry -- a little scary physics there, but the point is crucial for understanding the principle. It's an elementary point called Conservation of Momentum, which any first semester physics student should know.
What you want is a racquet that will give you the most ball speed for the least effort (Efficiency),
and which will not stress your elbow or shoulder (Elbow Safety and Shoulder Safety).
What you don't want is to put in a lot of effort on a wild shot that wrecks your arm.
But what if you put most of the mass in the head, making the racquet head-heavy? Wouldn't you then have a light racquet that hits hard? The light, head-heavy racquet will have a high swingweight, which is good for pace and spin. Swingweight is the inertia (resistance to change in motion) of the racquet as it rotates, and what this means in practice is that it's harder to whip, but once you get the racquet rotating (e.g. on the wrist snap of the serve) it will want to keep rotating when it meets the ball and will crush through, mashing the ball against the strings for better spin and pace. That's the advantage of the Hammer and the extra-longs. But in combination with light weight, there are these drawbacks on closer scrutiny: (1) a light and head-heavy racquet is bad for the elbow and shoulder, for technical reasons explained elsewhere; (2) it feels heavy and sluggish to position for volleys and returns; (3) the power comes from your effort, not the racquet, and you have to work a lot harder to get a certain ball speed than with a heavy and head-light racquet."
