Sealing aroudn a shower door

Just fitting a new aluminium framed shower door. The frame fits inside the 'doorawy' against laminate board. The instructions clearly say to apply caulk on the outside not the inside of the join. That just seems odd to me. I would have thought that the seal would go inside the join. Sealing on the outside means water will wick between the frame and the laminate and get at the fixing screws as well as just sitting there growing bugs. Anyone able to explain the instructions? I've done what they say and may write to the makers...
--
"Any PC built after 1985 has the storage capacity to house an evil spirit,"
Reverend Jim Peasboro
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I don't know - but here is a guess. If the frame mounting screws are along the midline of the frame, then applying caulk, which is also a strong adhesive, might seize up the screws, and bond the frame to the wall, making future replacement difficult. Also, I use pure silicone bath sealant vs std caulk, which is more prone to cracking and mildewing.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.