I'm inclined to count Backlash and overcasting as separate hits
Ouch, isn't that just a little harsh? I mean, I want my spellcasters to actually, you know, cast magic.
Well, contrariwise, if the situation is just that bad you can just do a Conviction+3 attack right off the bat, fill up your fourth Stress Box, and then proceed with lower powered hits from there on.
True, the only danger is filling your last slot and then getting hit by some stress and taking Consequences or getting Taken Out.
I like the option (suggested on these boards) of using spin to negate the initial point of stress from spellcasting. We see Harry do trivial spells that don't seem to take any significant effort to cast. People will be less likely to push spells if they have the chance of getting spin and taking no stress from the spell.
That's an interesting houserule, but I'd consider it carefully before implementing. Harry may cast some minor spells without any seeming effort, but that could just be the fact that it was an otherwise stressless scene and the stress went away at the end.
I do believe it was intentional. What I question is why example wizards are built Conviction over Discipline, I find the mental stress argument to be believable, but if you follow the stress progression it makes way more sense to just go for control. We have discussed this before but it seems odd.
Because you take a point of stress for each point of
difference between your Conviction and the power of your spell,
on top of the automatic point of Stress you get for Evocation.