Unspoken
In Zen, there is a strong tradition for not speaking about ones meditation and/or awakening experiences.
There are many good reasons for that...
When we speak about our own experiences, we can easily get attached to them. All experiences are fleeting and we can never recreate the same experience twice. So by attaching to an experience, we get caught up in an idea and start fighting with reality. Instead of being with what is and allow it to unfold fluidly, we resist what is and want it to be something else or lead to something else.
When we hear about someone else's experiences, the same thing happens. We may become attached to experiences (although now someone else's). We start comparing our own experiences with that of others, which gives rise to a sense of inferiority, superiority or just plain confusion. In either case, we attach to ideas and are lost from ourselves, rather than being with what is and allowing it to be fully experienced and fluid.
Turnarounds
Of course, for any statement - and view - there is an opposite which is also valid. There are innumerable turnarounds which also contains truth, and fills out the picture.
When we rest in the formless unborn - the space and awareness - which is at the heart of our everyday experience, we are free to engage in and bring forth any of these views, according to the situation. They each are valid, they each contain truth, and they are each appropriate in different situations.
In this case, there are also good reasons for talking about our experiences. With the teacher, it may be essential so they know where we are at. In other cases, it may also be valuable - as a way to explore and find faith in the process.
And there is less potential pitfalls if there is a good understanding of the ephemeral nature of these experiences, the lack of inherent importance and substance to any of them (even the most astounding and blissful), a practice of coming to and appreciating what is here/now, and a direct relationship with that which always is, distinct from the world of phenomena - that in which these experiences unfold and that which experiences these experiences - the formless unborn.