When it comes to direct sunlight there are different UV index depending where you live and here in AZ its the strongest in the nation. Initially when my Pothos on my 120 tank grew the distance to the adjacent window and under the shade in direct light the leaves withered and that was with 80% UV tint windows. After those exposed leaves died new thicker leaves grew and they did not wither when exsposed. All my Pothos stocks on my tanks are making the pilgrimage to the windows that provide their lighting. Some across the wall to adjacent windows and some across the ceiling to windows across the room. If I lived in a more temperate climate like Cali I would definitely build a long central canal pond outside stuffed with Pothos that all my tanks would drain to on one side (upstream) and draw from on the other side (downstream) using drilled overflows and returns. But here in AZ its just to hot in summer unless you build a deep pond.
yeah, i would definitely think the heat (off the charts) and humidity (virtually non-existent) down there would play a major role in killing pothos left outside to the elements. i also see what you're saying about the light... but it adapted and does adapt well to strong lighting. it's a tough plant.
curious though... what do you mean by 80% uv tint? i ask because windows with uv protection and tint are rated the same way usually. 80% (if that's what's listed on the windows or spec sheets) would normally be how much light or uv that's
allowed to pass. in essence this would mean it only blocks 20% of uv light. that's exactly why i buy 2.5% limo tint for my windows, blacking out the back of my fish tank, etc. ... because 2.5% tint essentially only allows 2.5% of the light to pass through, blocking 97.5% of all light. 2.5% is the darkest tint i've ever found, personally... and my room is a cave fit for a bat to rest comfortably if need be.
basically... it's completely possible that you'd get more light through your windows than i do on my patio... even with 80% glass.