Ok.. Let's run down this the last time.
When worn in combination with other pieces of armor, the form fit armor rating is added to the other armor’s rating (ignore the rule that only the highest value applies in the case of formfitting armor). When determining encumbrance, however, add only half the rating (round down) of formfitting body armor to the ratings of other armor when comparing them to the wearer’s Body x 2 (see Armor and Encumbrance, p. 149, SR4).
The subject of the sentience is a suit of form fitting armor. We can tell this because if the subject of the sentience is the form fit armor rating the sentience is the incoherent ramblings of a madman. Thus the rules described are true for a singular suit of form fitting armor, worn. They also create an exemption, or break, the existing rules for armor stacking as described.
You can't wear a form fitting armor rating, so it can't be the subject of the sentience. Yes, this is nit-picking lawyer talk, but it's also correct.
This is a minute grammatical issue, however, you seem to take far more offense in that I consider form fitting armor a badly written bit of rules for the game. That is a subjective matter but I feel my opinion is well warranted.
That smartlink is just as bad isn't really relevant to the current discussion, other then that you could add it to your own list of overpowered options, I suppose, but that the game has other items that all characters should invest in is a problem. The thing is, while a minor boost in offensive power or a fair boost in perception at no cost but having to write it on your sheet and remember to use it is a small problem, a fair boost to armor with only one option to get it and no choice of how to employ it is worse, in my opinion.
As you yourself pointed out, there are many options to get perception boosters. The only reason non-conductive armor is an item that I've called out already as overpowered.
I don't think either of us will lose any sleep if we just agree to disagree on this. Again, may we consider this line of discussion dropped?
Smartlink is less of a problem because there are characters that won't use it (many mages, adepts, even wired characters that don't focus on ranged combat)
Why wouldn't they use it, there absolutely no reason for someone to not use it and a lot of reason why they should, it's one of the biggest nobrainers in the whole game.
It's illegal without a license, they may have no firearm to use it with, they might prefer that their skill with shooting people -not- be effected by the Gremlins negative quality, they may be a two-guns ambidextrous gunslinger, ect.