Factoring crit as a source of damage if you don't have dex is the same as saying that a GC Paladin can still kill holy elemental enemies because you can still bash. No SP usage in the context of higher end dungeon is not an arguable point at all. You don't need to party in places that doesn't need you to use SP. In pvm party context, you BETTER be using SP or else you're probably not contributing as much as you should be in the party. heRO already ease your pain in this department with fish rather than using blue pot in every single go. If you're going to say that the free SP usage can be used to fuel endless true sight, it's not going to happen. I'm pretty sure I have the highest int out of every sniper in the server and I can't fuel endless true sight at my 85 int without items, or sitting down for awhile to regen SP.
lol Aaron don't quote me on int/dex build being "viable" as it's really not XD It only works for me because my sniper is only meant to farm in a few places that my SL cannot go XD; int/dex gives 0 item maintenance, last a long time in the context of gear hunting and is sufficient in mid level dungeons, but if you're hoping for pvm party, it's not a very good build to use.
Auto blitz beat is really a for fun only build, and no one's preventing you on using it if you find it fun. But if you're going to bring out pages after pages of math to talk about it in a min-max situation, then I'll sadly have to say, gravity does not permit any efficient PvM sniper build except DS spam or sharpshoot (and for hunter, nothing but DS spam.)