Blade Flexibility

Flexibility is how much a blade bends along its longitudinal axis. The amount of flex is primarily concern with the stiffness of the blade. Stiff blades will have little flex and vice versa. A lot of people use this term when they actually want to refer to the central deflection. Central deflection is how much a blade deforms perpendicular to its plane. The major component here is the density of materials used and the construction of the blade. This is what we call a hard or soft blade. A lot of people associate hardness with the top ply but it’s not just that (more on that later). So, we can have stiff but soft blades, flexible but hard blades and everything in between.

Is the flexibility related to vibrations that we feel in the hand?

Will the more flexible blades always have more vibrations or is there something other in play that determines vibrations?

No. You can see in the diagram that when the blade flexes, there is almost no movement near the thumb and index finger area. This means that there is no information being transferred to your hand. Central deflection (along with other modes of vibration) is the one that gives your brain information. What usually happens is that these modes are related. Normally, flexible blades are also soft, and stiff blades are usually hard (relatively speaking). There are also other variables involved, composite fibers attenuate vibrations in a way that wood doesn't, and that will give a completely different feeling. Those other modes I mentioned are what we call the annoying vibrations, fibers eliminate those vibrations so that you still have a clear feeling.

Central deflection controls our perceived hardness, what we call dwell time. More central deflection means more sensation in the hand. Harder blades give the sensation of less dwell time and vice versa. This is a matter of personal preference, power loopers for example normally don't like very soft blades because they feel the blade "holds" the ball too much. 

Thanks for giving me an intro on 'Blade Flexibility'.  I now understand a bit more.  I never knew there's so much (or at least some) physics, math and chemistry involved in how TT blades are made; how to choose one that best fits one's playing style until I started researching on blades.  For example: trajectory, low arc, high arc, pendulum, elasticity, density, pimple-spacing -> all these have to do with physics + math.  Booster, carbon, 3-ply, 5-ply, woods -> these deal with chemistry.  So many technical terms here!   :)   Wonder what I'd learn if I looked up on tennis rackets!?

Now that I've some understanding, I do agree it's just a personal preference whether you want to play with 'soft' or 'hard' blades.  It's all about style, tactics and playing strategy. I probably tend to play with a 'softer' or somewhere in between blade.

Medium rubbers on medium blades are good for medium players.  Which is 99.5% of us.

Butterfly example: Korbel + 2x Rozena

not-Butterfly example: Xiom Offensive S + 2x Vega Pro

There are > 1,000,000 medium-medium combinations like these.  All of them are good for medium players. 

Depends on style, dominant strokes.

Interesting... I have to keep this in mind.

serves including heavy backspin.  I can do chops and pushes depending on placement.  

However, what i'm weak at is to counter attack heavy backspin serves.  I want to be able to 

return with FH/BH with something like flicks or 'short' loops

back to the opponent side.  When I do this, the ball hits the net on my side (85% of the time)

and failed to land on the other side.  I know no two backspin serves are identical; they maybe

similar.  But in general and besides having the right TT skills, are there any rubbers that

will allow me to handle offensive attacks on backspin serves better than other rubbers?  If the type of

rubber plays an important role, please tell me what rubbers you use or would recommend.

Can someone out there who's better than me and offer some of your experience and insights on this?

Thanks