No, silicone is the thing to use here. The point is that as it gets
squeezed out, it fills any gaps between the two cut ends. The fact that
most of it gets squeezed out is a /good/ thing.

--
Grunff

Use both: seal the edges (I use two or three coats of solvent-based
polyurethane varnish) then clear silicone when fitting.

Just cut a worktop myself (how hard are these things! - I blunted 2 laminate
jigsaw blades cutting 1 length and a sink cutout!), the leaflet inside the
plastic cover said "it is good practice to put 2 coats of varnish 50mm
around all cut edges". The pipe cutouts in the white carcasses I just
smeared with white silicone (white to try and hide some of the chips the
jigsaw made )