Spandan Bro. this isn't the cause.
TAJ group shows the series which are profitable in HD or when thay are bound to provide feed to other country"s brodcaster.
They telecasted eng-sl series in HD as they had to give feed to Sky Sports
in UK and Cricket is more popular in England.
But they didn't telecast Pak-Sl series in HD.Because there seems to be no SPORTS channel HD subscriber in these two countries.
They telecasted Ind-Sl series in HD as it is profitable.
If they telecast Aus-Pak in HD ,who will see it?Cricket isn't so much popular in Australia and the timing of matches willn't suite.
Popularity of Cricket in Aus is same as popularity of football in India.