You can but not everyone is going to have their Thief be the one who manages to reroute the shipment. After they take the "spreading thin = bad" lesson to heart they might go for a pure thief and suddenly have to handle a combat encounter without the appropriate skills.
That reminds me, the traps skill really needs help too.
This is really the crux of the issue regarding metagaming. In isolation,it's easy to say "Oh, that's an easy check, you can have almost the right amount of skill from the very beginning", but the TG questline, by it's very nature due to the jack-of-all-trades nature of being a thief (i.e. anything from slick-talking charlatan, to anti-social infiltrator a la Garrett, to brutal thug) means that it's very, very easy to spread yourself thin. Doubly so when you look at the overall deficiency of skill points.
A particularly egregious example would be trying to steal the mantra from Antidas' palace; you need enough physical attributes to get up on top of the roof, enough sneak/lockpick to infiltrate and get into the display room, enough Traps to disable the triggers on the display case, and enough lore to get the mantra. Mind you, I've never succeeded in the last two steps that I've mentioned; I only know this exists due to others mentioning it, and was not able to find the mantra even with an optimized build due to lack of skill points.
Obviously, my character doesn't
need the mantra and it's simply a bonus, but the point is, that by investing in the skills to collect this special bonus, I can kinda fuck myself later on. That's because even if I were to be able to get the mantra, I would still end up hitting a dead end down the road because escaping Teron would be damn near impossible because I just spent all my points getting this stupid scroll, and I don't have enough leftto invest in either (a) diplomacy to talk my out of town or (b) combat to fight my way out of town. It's very easy to paint yourself in a corner like this in AoD at the moment, because the SP issue can create a domino effect where being unable to complete a quest means that you lack skill points to invest in skills to complete
another quest, and all of a sudden, you find that your build is unworkable. I think a lot of the complaints here stem from this.
Regarding synergies, they are a great idea in theory, but in practice you'll only use one weapon the whole game. SP are very, very scarce, and you need to save as much as possible, so investing in more than one weapon is a bad idea, because it presents an opportunity cost; points spent in a secondary weapon is points lost in learning defensive skills, crafting, alchemy, lore, etc. Also, because of the difficulty of combat (which, btw, I agree with), there is a disincentive to having a secondary weapon, because you won't hit a fucking thing with it. So you pretty much have to stick with whatever it is you've invested points into.
I know that this is something that you guys are addressing and that I have mentioned before on the ITS forum, where you devs knew it was an issue that needs to be resolved. I appreciate VD's desire to adhere to a philosophy where only certain characters can explore certain paths, but the gating is too severe. Which is a shame, because when you can explore content in AoD it's such a well-crafted, thought-out setting that had a lot of love put into it. You guys already have plans to add more skill points to the game, which is a great move that would alleviate metagaming and allow players to play around with skills more and experiment. It won't eliminate the issue of metagaming (I think that this is unfortunately inherent in the design, though the game's strengths make up for it, IMO) but it will at least make it much less of an issue.