Specific work for the splits

Reading around, I've noticed that a common recommendation for getting the splits is to work on them everyday. That's not the GB approach, I suppose (but may be wrong) because GB aim at this level is a gradual overall improvement of one's flexibility rather than specific and focused splits work.

Should I want for some weeks to work primarily on improving the front split, what kind of daily work would be recommended and for how long?
Ditto for the middle split (I can post a separate question if preferred).

Hi Guido , suggestions take place and can be considered only if they are contextualized. If I am 3 cm from the split goal it makes sense doing some work every day. If I am too far does not make sense perform hard work every day. the intensity of the session plays a big role, the technique used plays a big role because different techniques have a different impact on the tissues and on the central nervous system.

Grazie Alessandro. Here are pictures of my pike and left/right splits. I was warmed up but didn't do any stretch prior - at the end of the front split series it's better. I think on the split I can come to about a yoga block (mid height, not tall not flat) from the floor on my good side, left leg forward.

 

  

Hi Guido, your split shows the same mistake. the backward legs are turned out, it is pretty common in case of tight hip flexor.

As a general rule, the front and the back upper leg must be on parallel lines.

Thanks @Alessandro Mainente , I'll work to correct that. Any idea on how to improve the pike? My hamstrings are not the biggest limitation, it seems I just don't have the compression strength required to get chest on thighs. 

Your problem is the calves as in the 100% of people who needs a well locked knees pike.