Worked on a house where the guy had imported a dozen Portuguese craftsman to do the finishing, a lot of ornamental plasterwork and such. There were a lot of big double hung windows with 9 panes per sash, the guy doing the glazing used a 6" putty knife in a way that didn't involve all the rolling out the putty into a rope and then mashing it into the corner an inch at a time. I don't remember the exact motions used, I can't find anything about it on youtube, but the glass itself was used as the pallet for the putty. He'd put a lump on there and use the 6" edge to quickly fill the edges, kind of like how sheet rockers work. When the edges were filled he would use the corner of the blade and the slightly rounded side edge of the knife (not the 6" straight edge) to go all around the pane, mashing the putty into place, finishing the surface smooth and cutting off the excess. When he filled the edges, I believe the putty knife never came off the glass very much, so when he was done with a pane (the whole process took about 15 seconds per pane) there was a distinct repeated pattern of his knife movements left on each pane from a haze of putty, which would wipe right off, possibly after the mullions had been painted. I remember seeing that distinct pattern before on windows, and when I watched him I realized how they got there, so it must have been the standard old time way of doing it everywhere.