The thing is sometimes going blatantly in a wrong direction can sometimes give you a better perspective towards a better direction. Particularly if you can understand exactly why something is wrong, compared to something that is less wrong. If you can understand what is causing that difference then you have gained in scope for design. The 2011 Lotus was pretty lousy once they hit the development limit. And yet, they bounced back in 2012, without exhaust blown diffusers for a large part of the season, and they certainly got to grips with the coanda exhaust in 2013.
This rapid adaptation I think was due in part to their experience with their front exit exhausts, something that did not work as intended but ended up having beneficial consequences in the following years. I think they did something similar in 2014, played with a fundamental idea, saw what would happen, studied the results vs known quantities, and are using this to give themselves a leg up in understanding, and by consequence, creating development opportunities.
I'm pretty sure Mercedes did this as well, the only difference is they eventually ended up with a serious budget, whereas Lotus is...well Lotus, although no paupers, they're not known to be billowing cash like the top teams.