regarding candidates of double relevance

mol39

Dear Angus,
Thank you for your beautiful program.
As you have created it there are two possibilities regarding candidates: either you see none of them or you see them all (with ore without filter, that is).
I miss a third possibility.
When I solve a soduki (on paper that is) I do it in two phases. First I note only the candidates in each block that are rescricted to one column or one row in the block. You could call it "candidates with double relevance" as they are relevant to the block and to the row (or column) at the same time. I try to get as long as possible with the solution without noting any other candidates. If then these possibilities are exhausted, and the puzzle still has not been solved I go to second phase where I look at all candidates.
I find it more stimulating to proceed so as I find I get a better "feel" of the puzzle in this way.
So, I think your great program would be still more satisfying, if this approach to the playing was possible, either in a way where the player himself could input these "candidates of double relevance" or the program could offer them automatically.

Yours
Mol39, Denmark