yes - i know about it:) that's reason why in many cases i'm removing glass from windows to give a photos free way to get acces into interior:) PT engine always is calculating caustics if photos it going through refraction materials. But time to time (especially for close views) glass should be turned on to get reflections from interiors environment - is possible in this case to minimalize caustic calculations?
Yes, that's the whole point. There is refraction mode called hybrid, which renders glass with transparent shadows instead of caustics. Therefore you can have those glass walls there without slowdown. If you use Daily builds, then it is replaced with caustics checkbox. Lastly, You can have glass in windows as well. Best way is to create just planes, one polygon, without thickness, then create another glass, and set refraction mode to twosided. That is the fastest glass without any refraction, ideal for windows. So:
Solid: Refraction with caustics
Hybrid: Refraction with transparent shadows and no caustics
Twosided. Just reflection and transparent shadows. Imitates very thin glass, such as light bulb glass ;)