Vectored past the localizer

Doug wrote:
Several times, while under IFR flight plan and radar services, I have
been vectored to intercept the localizer and the controller was late
in turning me into the localizer. This usually happens when I need
about a 90 degree turn to the localizer. I have decided not to wait
for his vector and just turn. This has always been when the freq is
busy. There is a very small time window to turn (about 15 seconds), so
if the freq is busy, I can't request a turn before I am past, so now,
if this happens, I just turn. I told a CFII this and he said, ok, but
its not really the legal thing to do. I believe it is the safe thing
to do, and therefore legal. Any opinions from the group?

If you've been cleared for the approach, or given an instruction to
"intercept the localizer", then it's OK. If your last vector was
simply a heading to fly, then you should just keep on that heading,
even if it takes you through the localizer.

How is guessing what the controller wanted and then busting your
clearance based on that guess "the safe thing to do"?