I agree. Maple is hard to work with as it has a tendency to split if not fully aged then oiled after shaping and drilling. It is very dynamic and once moisture is introduced those forces are changed which can lead to the wood splitting.It must be very straight grained to begin with. I am not claiming to be an expert but I've been around different wood long enough to know that it can be unstable. This is why many builders use basswood, Alasken yellow cedar., sugar pine and such. They have longer cells and therefore longer grained so are less prone to splitting. Maple, being a true hardwood , is not but when it works it is better for plugs like darters because you do not need to weight it so much or at all. I've had darters split on me in the past. I hope this makes sense.