It doesn't work that way.
These days, T20 is dominated by spinners, but spinners who have mastered the art of spin bowling from First Class cricket - then they are exploiting the vulnerability of batsmen trying to maintain 10+ RR in middle & late overs and batsmen with little foot/wrist work. For Shadab, he has developed nothing for a leggi - no stock ball, poor line, pathetic length, not much turn or drift and he has a knack of bowling absolute rubbish every here & there.
In T20, sometimes batsmen will lob his long-hops to wards boundary fielders, but that's to maintain stats, not much effect. A Leggi must take wickets in T20 inside first 12 overs (Or 1st spell) so that the wicket matters & pulls down the run-rate. In LOs, couple of wickets in wrong time is worth 25 runs, massive in 20 overs' game - can't recall when Shadb did that last time. .
