I was also lucky to have a good OJT. I went to a smaller airport but this was much to my advantage. I could get in and do something and even passed a 50 hour check.
It does seem that those outside CATC do slag it off, especially once you have left.
And also, tolerant + caring those are the first 2 words that spring to mind when describing a mentor.
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ATCOs do it at the top of buildings!