I understand why a person would want to pick a lock but assume that I need to legally get through a locked door. Just a standard lock like my front door. I jam a big-ass slot screwdriver into the hole and pound it in so it is set. I take my longest pipe wrench (tons of torque) and trist the screwdriver. What would happen. I assume the pins would shear thus enabling the rotor to turn and I’m in.
Shearing the pins off is a known way of destructively “picking” a lock. I think some locks use hardened pins to help prevent that. On some doors, when you lock them, the knob or handle is still free to move just like it does when it’s unlocked, I assume to prevent an attack like that. No, it wouldn’t help if someone used a screwdriver and a wrench in the keyhole, but just trying to turn the knob with a wrench or hitting the handle with a hammer won’t do anything.
I’ve broken into a locked file cabinet by drilling out the lock, which also shears the pins.
It depends on the lock and the door. When my husband’s uncle couldn’t be found, concerned friends and family arranged to have his apartment opened. It took a locksmith (supervised by police) a few hours to get in.
The uncle turned out to be in a nearby hospital and hadn’t told anyone. He was pretty pissed about the damage to his door.
I assume the locksmith had to do more than Ian a big screwdriver into the lock and yank hard enough.
My locks could be picked (non-destructively) in a couple of minutes by someone who is good at that. And you could break through my door and reach inside and undo the lock in a lot less time than it took to break into Uncle David’s apartment.
You still might not be able to rotate the cylinder, the broken pins could just jam it up. As the video above shows you usually have to destroy much more of the lock to remove it entirely.
[former locksmith] We don’t pick locks, we drill and replace. We’d try to pick it if the lock itself was valuable or something like that, but otherwise picking is just something we did at the shop for fun.
OP’s plan would most likely just render the lock unopenable. It might break, but you’d probably break the door, too. You may as well just take to an axe to the door.
I once locked my keys in my car at a concert. I didn’t want to deal with a locksmith (pre-cellphone days so it would have been a hassle and I might have missed the show waiting for the locksmith). So I tried the OP’s idea: I jammed a flat-head screwdriver into the key slot and turned as hard as I could. The screwdriver turned but the lock did not open. The lock was destroyed of course. I spent some months entering the car through the passenger side door.
Remember a house usually has multiple weak spots, usually two or more doors and multiple windows. So you want to attack the point which is the easiest/cheapest. And for the OP’s front door try the key hidden under the flower pot…
If the lock and whatever holds the lock in place are bad enough, it might work. On my Thule roof rack removable lock cylinders go into holes on the rack and accessories, and then a latch attached to the cylinder holds a cover in place, or keeps the ski rack closed, etc. Turning the key rotates the latch, so things can be opened or removed.
However, the part of the rack that holds the lock cylinder in place is poorly designed or weak. Putting a screwdriver in the lock and rotating can move the entire lock cylinder so that the latch no longer holds things closed. The lock cylinder is still functional, and will work as intended if rotated back into place. The metal lock cylinder is stronger than the plastic pieces designed to hold it in place.
The YouTube channel LockPickingLawyer (which is, weirdly, really great) posted an April Fools Day video today but, I think, it actually really has relevance to the OP. (jump to 3:07 in the video if you don’t want the humor):
A few years ago I accidently locked my barn keys in the barn. I didn’t have a spare set. Luckily I had a battery-powered reciprocating saw in the house. I cut off the doorknob and then was able to easily open the door. A new doorknob was only around $15, IIRC.
Over the years my family’s business has been broken into a few times. One time, myself, my dad and my grandfather are looking at our smashed in back door tossing around ideas to prevent this from happening again. My grandfather wanted to put a hooks/hangers on either side of the door so we could drop a 2x4 across it. At this point in the discussion about how we could fortify the door, I reminded everyone that we could put a 2x4 across the door and they’ll just break a window. We could brick over all the windows, and they’ll cut a hole in the side of the building*. Granted “they” probably aren’t going to cut a hole in the side of the building, but if they want to get in, there’s plenty of glass.
*When I added a door from my garage to my backyard, I was surprised that it only took me about 2 minutes with a sawzall or angle grinder to make a hole in the side of my garage big enough to step through. I don’t know why I though cheap siding would put up a fight, but the only difference between that any the rest of my house is some insulation and a layer of drywall.
The Fire Department usually has this thing they call “the universal master key”. It can open any reasonably ordinary lock and door pretty readily.
Other wise known as a 250# muscular dude with a large axe and the legal authority to destroy the door getting through it. 
If that’s not quite universal enough they have the new-fangled v2.0 version that involves gasoline-powered tools.
Maybe, or maybe you just end up jamming the cylinder and seizing the lock.
There are frequently better ways to bypass a pin tumbler lock than either picking or drilling out the cylinder, often just by finding an unsecured window or a door that can be pushed far enough back from the jam to work the latch open. Most buildings are rarely as secure as people think they are on the basis of the front (or other normal) entrances.
Stranger
I had to call AAA for an ex who locked her keys in her car. Their method of entry was to wedge a small bladder in between the door and frame, pump enough air into the bladder to create a crack, cram a tiny fake rubber finger on a coat hanger wire into that crack and use the finger to push the unlock button from inside the car. Low-tech but very fast and effective.
The point of picking a lock is not to damage the lock or door. It’s not that hard (depending…) but you can always hire a locksmith if you do not know how to do it yourself.
Heck…it seems a battery powered angle grinder can defeat most things short of a bank vault.
I locked myself out of my condo once and hired a locksmith.
He used a bump key–a key cut like a sawtooth, and then a kind of rubber hammer thing. The bumps whack the pins so that they bounce apart at the shear line, allowing the lock to open.
Wasn’t particularly impressed with the amount of skill required, but it did open the lock without destroying it.