I believe the ratio is only 20:1 for stock jetting though. I might be wrong, but since the pump is gear driven, the amount it injects is a static number calculated based on the engine being stock.
20:1 is safe enough you can add quite a bit of fuel before you get past 32:1, and even 40:1 is safe too, so I dont think its a huge deal, but Im pretty sure as you modify and rejet, youre not keeping the same ratio.
Half of me thinks the oil injection is cool. It is simple, and when it works, it works. My girlfriends uncle has a blaster with a DG pipe and boyesson reeds. Thats all he has. Hes been running stock oil injection forever. We have been riding together for 3 years now and hes never had an issue. The bike is a 96 and I know all the parts are stock except for what Ive replaced on it, or the exhaust and reeds. It is cool he doesnt need special gas. Mine on the other hand is a PITA cause Im the only one who premixes sometimes, so I have to either take my own gas (they have a toy hauler, with a gas pump on it, and we usually just throw in on gas), or mix mine a gallon at a time which is what I usually do, a gallon at a time. Can be a PITA.
Anyway I wouldnt put oil injection back on my bike, but I dont know if Id take it off a perfectly working one either, unless I had plans to get into the engine.