Dragging the clutch slightly is how to launch hard. I used to be scared of doing it thinking it would instantly loop the bike but it actually loops harder if I don't drag clutch at 10k RPM or higher.
There is no dragging of nothing when you do it correctly. If you have lazy springs, worn clutch, or a sticky cable... then you are not applying the full force of peak torque.
There is also a weight transfer component.
If you are launching an R6... 10,000 rpms is kind of low.
Its really simple. You put the bike in gear, bring the RPMs up, situate your weight bias, and let the clutch lever fly. The sudden application of ~45 ft lbs to the drive train will lurch the bike forward you only disengage the clutch if your weight bias transfers incorrectly or the rear tire loses traction. Works the same if the bike makes 50ft lbs, or 65 ft lbs or 100 ft lbs of torque.
Well when you get above 85ft lbs the risk of failure on stock cast components is pretty high. Also if your bike has an extended wheelbase there are other nuances with a hand operated clutch.
Want to see how its done...watch a Supercross heat or main. Those guys are leaving in 2nd or 3rd gear because just the miliseconds it costs to engage a gear change and subsequent drive loss means the difference between 1st and 10th place into turn 1.