The boilermaker has a temperature gauge so you could use that to monitor your temperature and adjust as necessary.
I had thought about the same, but you may have issues maintaining mash temperature unless you are using a RIMS or HERMS system from what I gathered. You could always wrap it in a blanket or something.
I opted to go with using a cooler for my mash tun and I'll stick with using the boilermaker as a kettle. I did order mine with a false bottom though in case I decide to try it down the road.