I am guessing here, but maybe that is why there are smart Skippers. We can tell the AP what to do. Similar to what is needed with any other crew member. Except maybe the Admiral... But that's a different issue.
A smart skipper has equipment that has not been downgraded to idiocy by the manufacturer.
A smart skipper also has crew that does what he wants.
Therefore, in both cases, I'm an idiot.
:-D
Edit:
Seriously, no sailor with an AP and nobody on this board will disagree that "resume heading" is a fantastic feature.
I used it many times a day when I had it.
There was no reason to delete it.
It can be argued that track navigation is necessary in certain narrow circumstances, but I, like a giant number of others, sail the open Pacific Ocean. I only need to head towards the destination. In GPS mode this may mean some leeway but very little, given the nature of a GPS heading. Without the track, the AP was much more linear, and predictable.
Nother edit
Sorry, going off on a bit of a tangent from the original post.
A picture is better than words. Here's a professional artist's rendition of what I mean about track navigation (below).
The first line is what the SPX5 with P 70 does in GPS mode. It wants to always be on the track line, causing unwanted veering.
The 2nd line is what my old Simrad basic tiller pilot would do in GPS mode. If there were leeway beyond what the GPS was predicting, the pilot would merely continue to follow the GPS commands, and just adjust the heading more to windward.