Try it Molgrips (it's not my gearbox 😉 ). You'll find the decisive movement is better than being light. It doesn't require much force on a dog box but on a standard synchromesh box you have to use enough force to get past recalcitrant cones that are trying to do their job. That's a firm shove.
The only change I could make every time (and it has to be every time because if you fail the loss of drive is going to be hard to manage), was fourth to third. The bend tightens more than anticipated so you left foot brake to kill the understeer (still on the gas). The nose tucks, if it tightens more you brake more to get suitably sideways (still on the gas). The revs are now dropping (along with the power) and a lower gear needed to maintain the poise. No lift of the throttle, just change with a fast, firm, single movement. You instantly have more power. I can't think of any other time you'd want to clutchless change. (edit this only applies to FWD cars with enough rear brake balance)
assuming i've got it right (or near enough) its one of those things that, while it helps the car last longer, it doesnt help the driver at all? (where as blipping, and heel and toe, keeps the car/drivechain from jolting and pushing the car around)
Not quite. Your "blipping" is covered by the ddc method as you need to blip to get the input shaft up to speed, so it's "blipping" with extra mechanical sympathy and helps speed up your shift a smidge (if you're good, otherwise it takes longer to do the two clutch movements, you cock up the shift and ram it into gear without a clutch and all goes downhill).
Generally I don't but it's handy on downshifts with my 20 year old box where there's a slight notch. Even on the box new there always was a slight notch, it just depends whether the driver notices it I guess. My other half never notices and never does it. I replaced the box which required a full engine out job, so I'm very sympathetic to that gearbox now!
going back to what my dad taught me, many gems could fill a book - the most valuable thing was that "your boss will always be an idiot so it may as well be you"
Clutch? After driving all sorts of cars & trucks I really can't be bothered with this clutch/gearstick lark. Let machines work and people think. Automatics for me. Well, except when it comes to bikes. But then that's a whole other discussion I guess.