That's too small a gap, yes you would get misfires with that.
General "rule of thumb" for spark plug gaps is that you can change them but no more than .01, so for 0.054 range would be 0.044 to 0.064.
I tend to just go .005 up or down, so 0.049 to 0.059
But why change the gap at all..............well there are reasons, lol.
If you are a conservative driver you may want a slightly larger gap for a hotter spark at low RPMs(0.059), this can improve cold weather starting, and MPG at low RPMs, but when you get above 3,000rpms you can start to get misfires with the larger gap as the coil recovery time is shorter and can't build up enough voltage to spark the larger gap reliably.
Larger gap can also help if you are burning a little oil on a high mile engine.
Smaller gap works better if you are at higher RPMs most of the time, but can cause misfires on cold weather starts with rich mix.
The factory gap, 0.054, is not the optimal gap, it is the average gap.
Best thing, if you want to re-gap, is to change it, then drive it for a few weeks and then pull out 2 spark plugs, see what they tell you about combustion, nice light brown electrode is what you want to see.