"If the script gets too long, and does too many things, then it helps to have a debugger wouldn't you agree?"
Not really. It helps if you write clean code and put proper error_checking in it.
"You can put break points where you please and check values.Step in and out of functions."
Break-points are IF statements, and checking values is a simple print_r().
Stepping through a script line by line is the only thing that could be usefull.
"I used to code in Visual Basic 5 a lot, and miss the IDE ever since."
That is because Visual Basic is a piece pf MS-Crap that is un-debuggable without a special tool.
PHP is a clear and understandable language that has very complete error-reporting.
So far I have not had a single bug that I could not explain by just looking at the code.
... and the URL still is not working, I cannot even find cron.ru 🙁