The variable of endmass comes into play. Assuming uniform materials (wood is not) a smaller diameter shaft has less endmass to deflect the cue ball than a bigger shaft does. Now, wood varies from piece to piece so a 13mm shaft can deflect as much as a 11mm. You could also just unconsciously have been making adjustments for the deflection as a part of your pre-shot routine, and that's why you may believe your shafts don't have much/no deflection.
Many people say end mass, this is wrong IMO, despite what Mike Page & others say or think! his experiment with the pliers gripping near the tip did not allow him to long bridge it, plus it is huge mass compared to the shaft, and got huge deflection compared to no weight and long bridge. It is compounded complex dynamic mass, and depends on distance between bridge hand and butt hand. True there are lighter wood than others, which could make a difference, but the longer the bridge hand the less the CB deflection/squirt, until you reach the pivot point where cue deflection almost cancels out squirt and it looks like there is no deflection. With 11, or 10 mm tips approach angle to CB is steeper than a 13 or 14 mm, in another words tip has larger contact point for slightly elevated cue, hence additional swerve, this additional swerve almost always cancels out the squirt at 1st or 2nd diamond maybe less when speed is medium, slow speed swerve will be more,at fast speed squirt will be more. You have to know your cue at every inch of bridging, and every speed, and every distance between OB & CB, and worse yet at every tip of contact, or opt to no english for 89% of shots, that is even not a grantee that there will be no inadvertent english due to angled stroke and small tip.
So small tips has advantages and disadvantages, just as large tips, in pool, to be a pro or close to one your ball pocketing consistency has to be flawless, and the more you get basic trouble area out of the way, the less check list items you have to worry about at the heat of the moment, which is critical. Of course if you practice 8 hrs a day, those check lists tends to get ingrained in the subconscious,
but only if you really know all the knowledge/secret to shooting pool, that is knowing how to shoot the 4000 shots in pool, too much practice with wrong knowledge is worse to your game than no practice at all.