Oil primer over latex

Here's the deal: I replaced the planks on my deck last year with new pine and painted it with "self-priming" interior/exterior porch and floor latex paint. Of course you know what happened--as the snow came off the deck, so did a lot of the paint. Yes, I know what I should have *done*, but the question now is what should I *do*. Is it reasonable to scape off the loose stuff and put an oil-based primer over the remaining latex before repainting, or am I doomed to stripping/sanding off all the "old" stuff before priming? I don't plan on being in this house long enough to enjoy a super-quality, last-forever paint job (hence, my minimalist approach last year) but I do need something that will last at least a couple years.
Thanks in advance for your opinions.
Denny
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.