Informal vs Formal learning just interested on which learning method is quite effective. Some organiations depending on their structure will adopt both learning strategies or stick to mundane practices.
From my experience, I can tell that both formal and informal teaching and learning are important. Adopting these strategies is expected to link learning to students' lives and extend learning to different situations, and conditions.
From my point of view, formal and informal learning strategies occurs accordingly and they are very effective for learning. As I worked on this project, I have written an article attached to my profile. MSLQ are being used formal and informal way by teacher and students consciously and unconsciously which direct their learning.
Formal learning, on the one hand, is more useful and effective when it is used with forecasting strategies, in order to gain "tools" for future activities. Informal learning, on the other hand, is very effective when used with problem-response strategies.
From my point of view, this is due to the fact that formal learning is powerful to gain sorted and pre-existing knowledge, and informal learning to ask questions about specific problem in a reactive way.
So I think organizations should provide thoughful formal learning training AND set up a climate that easily allows exchanges and informel learning.