When I was running GoW bulbs, I used to run two 12 volt bulbs in series from the 16 volt ac supply.
This gave a 'nicer' light and they ran a lot cooler - they also lasted for ever at the 8 volts they were getting. Running them at the rated voltage would give a much shorter life, I found.
There would have been the issue that, when one bulb failed, it would have turned off the current to the other bulb in series with it, even though it was still capable of working. Therefore, I tended to try to make it easy to tell which were the 'associated' bulbs in that case, although simply being 'off' when all the others were 'on' was a good clue, and they tended to be near each other, of course. You would still have to discover which of the two was the failed bulb. But, in the end, none of the bulbs running at 8 volts ever failed.
LEDs are definitely the way now, though, much more reliable and efficient.