If it helps, try to think of evolution as just walking. What you refer to as "micro"evolution could be seen as taking a single step. What you refer to as "macro"evolution could be seen as taking a kazillion steps.
Nobody is claiming that you could walk from New York to California in one giant step like you implied with your very loose definition of "macro"evolution. But given enough time and enough steps, one could literally walk from New York to California.
The fat man walking (aka Steve Vaught) proved this.