Does "tinkering with" mean "mending carelessly"?

tin·ker
[ting-ker]
noun
1. a mender of pots, kettles, pans, etc., usually an itinerant.
2. an unskillful or clumsy worker; bungler.
3. a person skilled in various minor kinds of mechanical work; jack-of-all-trades.
4. an act or instance of tinkering: Let me have a tinker at that motor.

The verb tinkering usually is associated with hobbyists who take apart and rebuild electronics like calculators, computers, etc... to see what makes them tick. Other people maintain and/upgrade their own cars by tinkering with the car's motor for example.

Quote:

tin·ker
[ting-ker]
noun
1. a mender of pots, kettles, pans, etc., usually an itinerant.
2. an unskillful or clumsy worker; bungler.
3. a person skilled in various minor kinds of mechanical work; jack-of-all-trades.
4. an act or instance of tinkering: Let me have a tinker at that motor.

http://dictionary.reference.com/browse/tinkering?s=t
The gist of this definition is basically about amateurs doing their own professional work without the professional training/expertise. This definition gives a darker negative connotation to the word of which I have never heard before. I often associate tinkerers as a positive and creative phenomenon.

The quote you gave leans towards the dictionary's traditional and negative definition. In a sense, mending carelessly could be a somewhat accurate take on the "tinkering with" term.

Though, the quote you gave here also gives a menacing tone to the practice of "fixing" the global system by covering up something underhanded and making it look like it supposedly was done for the good of society in general. I prefer my positive definition to this ironic use of the term. As anyone who has access and the ability to change the global market can in no way be deemed an amateur even if they're incompetent in their process.

Great question oristarA!

Engineer is correct.
In this context, Tinkering is making little changes, lots of them, in order to make something complex just a little bit better OR it could mean that "they" were making lots of small, but USELESS, changes in order to look like they were actually trying to solve a problem or condition.

You could also use Tweaking as in "Those engineers were tweaking the components through most of the night.
Or
The program simply would not operate until the software was tweaked and retweaked.

Tinkering has a sense of playing or toying with something, someone who is tinkering with their car's motor is more likely to be making some small, perhaps frivolous, changes. He or she is not dropping in a new supercharged engine.

Joe(Don't tinker with my tweaker.)Nation

i may seem shy and boring at first but when you get to know me im really fun relaxed and love to fool around and b little crazy (in a good way). I dont drink nor smoke nor wear high heels and party in mini skirts and tops. I dress normally in jeans and cool tshirts, have brown hair to shoulders and wear normal make up. Im not overweight (i weight 100 pounds) nor ugly. I have friends, but none of them r guy friends. So this all proves that im really normal and thats why i cant figure out- why doesnt any guy like me in any way? All my girfriends and cousins have tons of good male friends who they hang out and fool around with, but all my life all guys ever did to me is tease me. I have no idea why and i thought in high school i can start over, but it started again. They just dont like me in any way and i never did anything to them!! And i wont even talk about having a crush on me, coz that never happened amd honestly i cant see it even happening. Every time i had a crush on sb id end up heart brok