Detect paired w/ other detect commands broken

We used to be able to use the /execute detect command in a chain like this:
/execute @a ~ ~ ~ detect ~ ~-1 ~ stone 0 detect ~ ~-2 ~ stone 0 say I've got 2 stones under me yay

It worked as far as I remember and was used to test for multiblock structures.
Seems to be broken now... please try to replicate. Fix appreciated.