Hello A4,
I was probably nor too clear in my earlier post.
The primary concern is:
At the time of GA the fuel flow indicated is with referece to the current ALT which is probably a few 1000' Amsl.
Now all through the subsequent climb and cruize the fuel burn would be at a much higher rate.
and the rate of increase is not leniar in that, say the increased f/f at low alt is double the normal, during climb it could be thrice the normal.
IMHO