I've recently had this very discussion with a group of my mates at a trackday, all of them had done the L1 & 2 Superbike School (I haven't) The general consensus was that the school days had told them what to do but only doing trackdays had actually improved their technique & yes, those improvements had transferred to their road riding.
All of them said Brouggy is a bit of a wanker & loves to overstate the value of each "tip" & over analyses into WAY more detail than is required, all said that if he just said "try this, this is how you do it" & let them out on the track to practice it, the results would have come much faster. They all reckon he gets far too hung up on the theory & wastes too much time crapping on when they could be out on the track learning.
The boys reckon all they got from their L1 & 2 experience was;
1/ Get all your braking done in a straight line.
2/ Keep your head level & look ahead & through the corner.
Apparently, these pearls of wisdom were the only things that made any difference to their riding (& yes, they ARE both very important)
From a non school attendees perspective (mine) I think they've wasted lots of money on something that any decent racer could have told them in less than 1 minute & they're all still slow!
Do some trackdays, follow faster guys around, practice the above 2 tips & you'll be flying in no time.
That'll be 2c thanks.

Ex T.K.A. ZXR 750 RR
ZXR 7/9 L3 Streetfighter
ZX9 C Trackbike - ex Maccarocks & Slow & Wobbly... still a weapon!
Plus a ZX7 & a few ZXR Ls & ZX9 Bs & Cs in various stages of completion.