...Right, had Obama acted as I suggest, his important achievements might have ground to a halt. I guess you're unaware that Obama exercised his veto power twelve (12) times, and it was only overridden that one time.
Normally a presidential veto is a bargaining ploy. The president doesn't like something in a bill, so vetoes the bill. Congress could override the veto, but it's true, it takes time and trouble, so what they do instead is bargain with the president over the contentious portion of the vetoed bill. When the revised blll goes back to the president, he signs it, and the government carries on.
The important point is the president cannot take away the right to govern from the Congress. In the end, Congress can initiate bills, and see them through, and there's precious little the president can do other than delay the outcome.
And as someone pointed out above, the president can't initiate bills, only veto (delay) them. So trying to run the legislative agenda from the White House is not really possible.