I agree with players jumping into test from T20 league. Having said that I am not sure it had made much difference in the test format when it comes to bowlers doing well when playing away. It may have made difference for visiting batsmen because adjustment is huge, but not much of an adjustment for home team batsmen. I also don't think Wasim played in era which was much tougher or easier. We just had 3-4 good test teams in any era.
In the last 55 years, we have only 15-16 pacers with below 25 average with 50 plus wickets. I wouldn't necessarily take the list in any order and start ranking bowlers. This list is also not eveyrthing. But
just a quick look at this list shows that we don't see many bowlers coming in this list due to batsmen jumping from T20 to Test. If it was really making difference we should have seen lots bowlers in current era showing up here. Reason is simple, batsmen are playing in their familiar conditions.
Despite our impressions, test cricket has changed but not by much. Shocking batsmanship is surely visible time to time, but T20 influce also means that batsmen can dominate in big way as well. Early era had tail as walking wickets but now tails can score runs as well. So lots of things evens out in test format and as result we don't see lots of pacers appearing in this list after T20 started.
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