Feature request

[Matzi Kratzi]

I really like ediff and almost always prefer it.

There is however one feature that I really would like it to gain (or
really would like to know how it can already be done):
One of the for-money-competitors gives the user the possibility to
help the tool by pointing to sync lines in the buffers. That way the
diff can become much better.

Is this possible already?

Kind regards
Mats