If your anything like they are in Germany using what I consider real short and blunt pegs couldn't a solution to blow-out or getting stumped against the far side of the mortise as a consequence of less than perfect alignment be more peg length and bevel it over the first 1/3 of that length? This is sort of the standard of practice as you call it here in my area. That's a good point about uneven stress on the tenon in the case of an angled peg hole.