1) From the power of point to circle, we have
PA/(BIF)=AF⋅AB and PA/(CIE)=AE⋅AC.
But it is easy to see that AF⋅AB=AE⋅AC then A belongs to the radical axis of two circles (BIF), (CIE).
Hence, A, D, I are collinear.
Denote J=AH∩BC then AD⋅AI=AH⋅AJ which implies that H, D, I, J are concyclic, then HD⊥AI. Then by considering the radical axis of three circles (AEF), (JFEI), (JHDI), we can conclude that BC, HD, EF are concurrent.

2) Using sine law in some triangle, we get
sin∠BIDDB=sin∠BDIBI=2sin∠ABCBC
and
sin∠CIDDC=sin∠CDICI=2sin∠ACBBC
Then
DCDB=sin∠ABCsin∠ACB=ACAB=LCLB.
This implies that (ADL) is the Apollonius circle of triangle ABC.
Thus KCKB=ACAB or ABKC is the harmonic quadrilateral, then AK is the symmedian of triangle ABC. Hence, AI, AK are isogonal conjugate in angle ∠BAC, also in angle ∠EAF. Since G, D∈(AEF), we have GD∥EF.
Finally, AS is the external bisector of the angle ∠BAC, also of the angle ∠EAF then T is the midpoint of major arcEF. From these, we can conclude that TD=TG. □