It's been a while now, but I made a very nice large drawknife from an old file. I heated the file in my propane-fired furnace, just laying in there kind of sideways like, and beat it into shape. You might call it blacksmithing, but that would be too generous. Then I finished the shaping and smoothing with another file (because the old one was now annealed) and an angle grinder.
Once I got it pretty close I heated it back up again and finished by plunging into oil. I recently learned that using any old oil is not the best practice for a number of reasons, but sometimes we need to make do. I didn't bother tempering it.
As a final step I used a flap-disc on an angle grinder to sharpen the edge and honed it to a razor sharp edge with a stone. I welded some handles on, and I'm still using it today.
So, yes... it does work. I agree that for hobbyists you should try to have multi-purpose tools when the use is seldom and it can still get the job done.