i say, if you want both, spend a talent point in both, or use one spec for SMF and your other spec for TG. I like the separation.
anyone who specs both is beyond terrible
Making blanket statements like that isn't helpful to anyone. I could just as easily say that anyone who doesn't just dual spec into TG and SMF is beyond terrible. Neither statement is necessarily true or false.
What would they be giving up? Deep Wounds? Incite is more valuable, imo, than Deep Wounds, especially with a 5% crit chance baseline at 85 (by all reports); I think it's okay to give up a couple of points in that talent. It's not like you aren't wasting points in Field Dressing or Blitz to get Deep Wounds anyway. Or you could go the other way and give up two points in Incite for 3/3 Deep Wounds.
You can say Field Dressing is useful, but then I'll tell you to stop standing in fire; and Blitz is pretty self-explanatory. But hey, like I said, you can just dual-spec into TG.
I like the differences; I like the price you have to pay in order to want to take my SMF weapons, or if I want to take TG weapons. What do weapon skills and doing away with them have to do with SMF and TG? None that I can think of.
I think it's a meaningful choice right now, which is evidenced by this very thread. I think those are few and far between right now, and in this case, I like the choice.