Oh yes, there "will", make that """WILL""" be more oil dripping/spraying out the exhaust and more oil on the operator and more oil on the mechanicals.
As the cooling system on these engines is fixed i.e. pegged to the surface area available for heat transfer, the only other method of heat extraction is through thermal transfer to unburnt excess oil, hence when riding in shorts, your legs will get attacked by scalding droplets of hot oil and socks, shoes and jeans will essentially become a dirty rag.
20:1 isn't necessary if the engine is lightly loaded; rarely seeing high duty cycle i.e. putt, putting around.
In such a scenario, you could easily get away with 40:1, even 50:1 if gently cruising about, using cheap 2-stroke mineral oil.
My situation though is perfectly suited to cheap 2-stroke oil because i'm using it for heat extraction, not for any extra lubrication.