smooth is deceptively playing word games again.
when he says 35% he is talking about the current coin supply not the total coin supply. i guess that means that 15-20% of moneros "current coin supply" was instamined.
0% of anything was instamined on Monero, and you know it.
If you want to express the effect of the deliberately de-optimized miner in terms of the current supply of monero it would be around 2.5x (roughly 1/2.5 of the nominal total coin supply currently exists), so probably <2.5%.
If you want to express the effect of some people optimizing miners better than others, that might be as much as 12.5% or more if you consider that it goes on forever (for every coin, nothing special about Monero).