There is a seventh step to maximizing a manual transmission's potential that most seem not to be aware of- optimizing the clutch's engagement rate. Excessive clutch torque capacity makes it possible for sudden engagement of the clutch to send huge spikes of energy back and forth between the engine/transmission/drivetrain/tires. Those spikes occur not only during launch, but can also occur after the shifts. Sure an accomplished driver can minimize the effects manually, but the more excess clutch torque capacity there is, the narrower the driver's margin for error will be. If you have a weak transmission, it may not take much of a driver error to break it.
Here's a link to one of my webpages with background info on how the clutch can greatly intensify the energy spikes sent thru the transmission. The page is aimed at drag racing, but the same general forces have the potential to wreak havoc on your transmission and tire contact patches any time the clutch is engaging... https://grannys.tripod.com/clutchtameruniversity.html
In an ideal world, the proper way to minimize the problem would be to install a clutch that is ideally suited to the application. The problem with that solution is that the steps between different levels of clutch capacity are fairly large, usually forcing you to choose a clutch with too much torque capacity just to make sure you have enough. Fortunately if you must choose a clutch that has excess torque capacity, there are external devices that can make an overkill clutch a better match to it's application.
Many oem's actually use a "clutch delay valve", basically a one-way restriction to slow clutch engagement for the purpose of protecting the drivetrain. There's also lots of u-tube videos out there dedicated to removing those clutch delay valves. You can get away with small amounts of simple in-line fluid restriction without much trouble, but when you restrict fluid return from the slave to the master in quick successive strokes like racer's do, the master cylinder's internal return spring causes additional fluid from the reservoir to be drawn past a collapsing cup style piston seal. This is not a problem during casual driving, as the additional fluid drawn past the seal has time to return to the reservoir before the next shift. But when clutch pedal cycles come in quick succession, that excess fluid does not have time to return thru that small compensation hole which in-turn causes an increasing pump-up effect that messes with driver coordination. In the end the driver thinks he missed a shift, but what actually happened was the pump-up effect caused over-stroking of the slave, which in turn produced an rpm flare caused a delay in the clutch grabbing after the shift.
Here are some examples of aftermarket flow restriction valves that function much like the factory delay valves, except these aftermarket versions are adjustable...
...Tilton Flow Control Valve is a flow restriction device that allows you to adjust your clutch's engagement rate. You can read about it as well as the reasons that you might want one here... https://tiltonracing.com/product/flow-control-valve/
...Clutch Masters Flow Control Valve does basically the same thing as the Tilton, you can read about it here... https://clutchmasters.com/i-30500576-flow-control-valve.html
...Magnus Launch Control Device eliminates the pump-up effect by adding a solenoid bypass parallel to the in-line fluid restriction, making the restriction path active only during launch. You can read about it here... https://www.magnusmotorsports.com/product/magnus-launch-control-device/
While flow restriction devices are effective for reducing impacts to the transmission, a common problem with all the flow restriction devices is that they all restrict fluid return flow during the entire pedal release cycle- including the deadband area before the clutch actually begins to engage. This can be a big deal if you are a drag racer, as delayed travel thru the clutch pedal's deadband area during launch also adds to your car's reaction time. The typical "fix" for the resulting slow reaction time is to pre-load the clutch against a hand brake prior to launch, which serves to miminimize the clutch pedal's deadband travel. The problem with that in a drag race scenario is that that pre-loading the clutch causes it to heat up. If the opposing racer knows you are pre-loading the clutch prior to launch, they will likely delay their staging to put additional heat in your clutch, which will likely cause your pre-loaded clutch to pull thru the beams pre-maturely resulting in a red-lite.
The ClutchTamer is a clutch engagement control device that is unique in that it controls pedal return rate instead of fluid return rate. It does this by acting directly against the pedal itself, which completely eliminates the problem of drawing additional fluid past the master cylinder's piston seal. Also because the 'tamer does not become active until after the pedal has passed thru it's deadband area, reaction time of the car does not get delayed. The need to pre-load the clutch to improve reaction time is completely eliminated. You can read about my ClutchTamer device here... https://grannys.tripod.com/clutchtamer.html
In addition to the ClutchTamer, I also make the Hitmaster 2-stage clutch control device for drag racers. My ClutchTamer device I linked above is a better fit for the typical Grassroots guy.
Grant