A few thoughts racinating from the simple act of hammer restoration:
after time all wood will dry out and shrink, starting at the ends. for safety reasons alone it is so important to condition the eye wood in a soak in linseed oil so the head doesn't come loose.
(i paint the tail end to keep it sealed, but if you persuasion is for absolutely no flash then a soak at both ends does the job)
a properly cared for tool will act as a record to your value.
the absolute best tools are those that have helves worn smooth by use of the owners hand.
conditioned wood worn from the hand is how the handle mirrors the patina from oil on the steel to show a complete description of how the tool was cared for and how much valued work was achieved.
the longer the tool is cared for the more time is spent with the tool.
a simple glance at the tool will show your history.
and for all of those that "make" will be able to decide, right there, where in the ranks you stand.
not sure where to start with describing this cobble job but i will jump to the end
and say, "probably not safe"
(more than two wedges, cracks in different directions and chunks of wood missing)
The first step to the restoration process is to drill out the handle in the eye.
actually i cut of the handle (about 1/4" from the head) so i can drill from both sides of the eye.
when i first saw this, i couldn't help but to think damn, this is going to break a drill bit.
fortunately it did not.