David Vizzard's latest book HOW TO BUILD HORSEPOWER has some great info on why and where the LSA should be for different motors. In a nut shell, it is about intake valve to cubic inches,valve to valve relationship, combined with a bit wider LSA for high compression. Our big blocks suffer from small valves to start with. They are also parallel, which doesn't help. Then we stroke them to the limit and reduce the overlap flow needed per cubic inch even more.
When you get into large engines there is a need for more exhaust flow, and in my case with 528 cubes and 7100 rpm shifts it works out to 110 to 112 LSA IF it has more exhaust duration. Because I have over 15/1 compression and poor exhaust flow for the cubes and fuel, it works. The cam timing is brought back to more like a 110 or 108 LSA by advancing it combined with the extra exhaust duration. If you look at the card numbers, my cam current cam which is 284/296/112 installed at 108 looks like a 108 LSA cam with 284 intake and 284 exhaust duration on all three opening and closing points but the exhaust opening point.
With very high compression, the pressure in the cylinder decreases at a high rate compared to low compression, and for that reason opening the exhaust early is less detrimental than the gains from more exhaust flow.