Our portfolio is positive even with the new loans, so it is unlikely we would be forced to sell, including in case of job loss. If we did have to sell (for instance, permanent disability) the portfolio is sustainable enough that we could sell in a controlled way. It wouldn't be a fire sale. We aren't as close to the wire as a 100% borrowing might suggest - we actually have a fair bit in savings, but we also have some major overs and unders in the next six months that we need to manage.
And in any case, selling either IP#1 or IP#2 would realise enough to clear both the primary mortgage and the crossed loan. So the arrangement wouldn't block selling just one, or force the sale of both, which as far as I know are the only reasons people avoid crossing.
In other words:
IP#1 - value $320K - first mortgage $245K - crossed loan $18K.
IP#2 - value $290K - first mortgage $208K - same crossed loan $18K
The exit strategy is to sell IP#1 and clear first mortgage and entire crossed loan, leaves $57K and IP#2 released from the crossed loan. (Or the same in reverse for IP#2).
We didn't do it without crossing because we didn't want to incur LMI for such a small loan by putting it against one property only (we would have gone above 80%), and we couldn't do separate smaller loans because the bank has a minimum home loan of $10K.