Almost ALL players under 100 break standard are holding WAY TOO TIGHT especially on long pots, power shots, and screw shots. This tension pulls the cue off line and REDUCES power.
A client in The Snooker Gym Community on Facebook commented:
‘Does anyone have a tip to help prevent gripping the cue too hard / tensing on follow through? It's hard wired and I'm struggling to re-train my body to stop doing it, particularly during a match.
Even thought of adding a thin layer of plasticine to the butt section!’
To dissolve this habit, I suggest you practice delivering with gradually increasing power with no cue ball, then with the cue ball, then a simple pot, then a tough pot etc, and see which step provokes you to over tighten. Then you focus your practice on that type of shot to increase your range of shots where you can hold the cue like a loose hand shake (imagine holding a raw egg or a little bird, or a child's hand... you hold it securely but not too tight).
Over tightening is done subconsciously to exert 'control' over the cue in reaction to the player seeing their cue moving 'un-straight' (ie SIDEWAYS!). A match will exaggerate that uncertainty as there is more riding on the result of each shot. So ultimately, it is not about 'not holding the cue tight any more as that is the SYMPTOM of lack of cue control.
The idea is to build up your cue control to the point where you can cue straight & smooth for the full length of backswing and delivery whilst holding the cue with the same 'Egg-grip' tension. From here, you will begin to see a downside to over tightening and a lack of ability to cue straight (required for potting) and smooth (required for speed control) - at that point there is no advantage at all to over tightening which is when the habit tends to disappear. So, address the CAUSE and not the SYMPTOM.
Let us know how you get on!