Hijack: no matter where you stopped in WoT, I highly recommend jumping forward to Brandon Sanderson’s last three volumes (I skipped four books myself, and don’t regret it). He fixes virtually every problem with the series, including the one you mentioned. His books are fun.
And I had figured that Roy’s brother drowned or something like that. I guess we now know why a guy with Roy’s INT became a fighter.
Wise words in the 2nd to last panel.
It’s interesting to look at 496 and 944 together. Even though there haven’t been any overt changes in the art, you can definitely tell that there’s a difference.
I wonder if it was Roy trying to be a wizard who had an accident or Roys dad who had the accident and then wouldn’t take responsibility. Either way, it could explain much of the animosity between them. I just noticed that 496 is titled, “Responsible.”
While it would be quite the plot twist to find out Roy has a level of wizard that he abandoned after the death of his brother, the line in 496 of “I was just a kid. It wasn’t my job to watch the grown-up” and “Dad just shushed me. He never listened to me when Mom wasn’t around” seem to indicate it was a power-hungry Eugene that killed his own son experimenting. Not acknowledging it, in fact blaming his other son for the sins of the father, would certainly put a wedge between them and drive Roy away from being a wizard. With a Fighter Grandpa, that just directed him to that class instead of some other class.
Has it ever been even hinted at that Eugene caused Roy’s death? That sure changes the way I look at that character. I’m surprised it was never mentioned in the afterlife, or during any of Roy and Eugene’s squabbling.
I thought 496 made it pretty clear that Eric (not Roy) died because of an experiment by Eugene that went wrong. 944 makes it even clearer and indicates that Eugene never even accepted responsibility, possibly even blaming Roy.
Gah! I meant to type Eric.
Every damn time! Even when I just go back to check dialogue when someone mentions something about it. EVERY TIME! 
Like Measure for Measure, I assumed that Eric had died due to some other accident or incident where Eugene discounted the threat even if he wasn’t directly involved. Really, the way Roy says “It wasn’t my job to watch the grown-up” instead of “…watch dad” made me think that some other third party was involved where Eugene dismissed Roy’s misgivings.
The flashbacks when Xykon destroys Roy’s sword (it got better!) show both that Roy has some magical training (“You’ll be back to cantrips in a week!”) and that he’s always had melee-centric tendencies even as his father tried to push him into spellcraft.
Also, I just noticed that that must be Eric in the one panel
The pertinent bits of information all seem pretty clearly in place. Eugene was conducting an experiment of some sort, Roy foresaw the possibility of danger but didn’t speak up as much as he could have, something went wrong and Eric was killed. I’m not sure that adding in third parties or intrigue or other details really adds much to the drama. It definitely puts their relationship in clearer focus, though. Roy blames his father and his arrogance for what happened but also blames himself for not taking charge of the situation. Eugene sees the incident as an unfortunate accident, but recognizes that all meaningful research comes with some risks an an extremely bad stroke of luck doesn’t mean that it was a mistake in the first place. It’s certainly possible one side is right and the other is wrong (Eugene was being utterly reckless or even using Eric as part of the experiment; The experiment actually was very safe but only went wrong because of a truly unforeseeable freak occurrence), but more likely than not its the kind of situation where both parties can both be kind of right and kind of wrong, but years and years of argument and resentment has calcified both of their views.
Also, in OtOoPC when Roy visits Eugene’s grave he makes some quip about his father saying he’d “give up Divination over his dead body” (or something like that - I’m going from memory); the point being that Roy at some point was indeed studying magic.
I (at least) was saying that I thought, based on the strip with Eric, that there was some other incident. The recent comic makes it clear enough what happened. People aren’t adding in third parties at this point, they’re taking them out.
Also, hen he recruits V in the same book, he shows some very precise technical knowledge of fireballs. But I doubt that Roy’s got an actual character level in a spell-casting class. Probably just some skill ranks in Spellcraft or Knowledge: Arcana.
I don’t think that Roy himself ever actually pursued magic, but rather that his father was always trying to push him towards it, and Roy consistently refused.
In this strip, Roy’s grandfather calls Roy, “a single classed fighter, just like me.”
So, are the Fiends still monitoring V? Are they aware that he’s come clean to Roy? That they might be planning for the next two soul grabs? Sabine busted their TV, so I wonder if they’re still able to keep tabs on V. My guess is yes, TV or no, they have some way of keeping an eye on him. Still, it would be interesting if they experienced a brief delay in their surveillance of V due to the broken TV, and thus were not privy to V and Roy’s discussion. That seems like just the sort of thing Rich would keep track of as a possible lucky break for our heroes later down the road.
Probably had some How Not To Get Fried By Your Own Caster : Positioning 101 courses back in Fighter College, yeah 
I would imagine that the fiends are perfectly aware that V might well tell the other members of e’s party, particularly considering the parting shot about “what are you gonna do?”. Whether Roy can factor this into the team’s plans - and whether the fiends can anticipate Roy’s counterstrategy, whatever it is - is what makes the story interesting.