Looks great....but....over the years we have used many Silicone types. The problem I see is that as Andy has indicated the floor does flex - even when walking on most boards they will flex - silicone if flexed will eventually pull away from its adhesion point - and ANY moisture what so ever (air - humidity) will add to the problem - a silicon grout may have been a better choice. If it is stuck on their good with no flex then you might be looking at cracked tiles down the road.
We have laid tile many times and if not done correctly with some pretty serious non flex underlay you are going to run into issues sooner than later.
But you know it is like gardening - the fruits of your efforts are relished for a bit of time - then you wait till the garden fills up with weeds again before you are back on your hands and knees.....
But she sure does look nice.