I’d be careful about applying treatments to your teak deck. They undoubtedly make the teak look nicer, but my teak deck is suffering badly from treatments applied by the previoous owner. The cockpit locker was full of them! I spent many hours on my knees over the winter sorting out areas on mine where either the teak was lifting or the caulking needed replaced.
Many of the treatments claim they don’t adversely affect the teak, and that is true. However, what they do is affect the black caulking, making it hard and brittle, and shrink.