That's wrong. You need to check out the gear section right where it says things like Str required. You can't carry around a huge ass gun if your weak.
Of course you can. You just need to be willing to accept the to-hit penalty, or to use a smaller gun. Like a pistol. The real problem with a low Strength is in carrying stuff without a penalty - armor and weapons are HEAVY, no matter when or where you are.
So your wrong about Str being a dump stat. Also, even in a modern day setting, melee and hand to hand combat CAN happen and then you will be sorry you tried to use Str as a dump stat.
Pistols can be fired in melee, using your Shooting skill, against the enemy's Parry. Since you used Strength as your dump stat and bought a gun, your Shooting is probably much better than your Fighting since you expected to use it more. As well, you've had more points to toss into Smarts, Agility, Taunt, or Intimidate, so you can Trick or ToW your opponent and possibly shake him before taking one step away and firing with your shooting against a TN of 4, against a pre-shaken opponent.
Dumping Strength is a completely viable tactic, in any setting. When there are guns? Even more so.
Nor would a decent DM allow such cheesy combos suggested here.
Some of them are totally okay - the Obese, Elderly, Fleet-footed wizard, for example, is totally a staple of non-gritty High Fantasy. The Reach weapon and the First Strike is even suggested in the main book, even if, as Clint points out, it's not as nasty as the poster thought it was.