I guess I used incorrectly the word opportunist. What I wanted to mean, on other words, that certain players tend to play on small tournaments where they get points easily. That is part of their strategy and if the do it in a different way probably they would not be ranked where they are right now. That's my point of view.
my problem was not the word, but precisely what you describe, which imo is wrong on the ATP main tour (it exists in challengers but the structure of the main tour makes that optional tournaments other than grand slams and mandatory tournaments have a too small weight, and also the difference between the quality of the tournaments is not as high as in challengers ; besides, the factor which people keep on never considering in those so-called "strategies" is money
, not rankings), but well clearly I can't do anything against Lenders' persuading power