Van Halen has run dry. If Ed really had "10 albums worth of material" they wouldn't be re-using songs with different singers, Like Spammy claimed "Can't Get This Stuff No More" was.
If Eddie really was writing as much as he claims he is, why would 3 of the last 5 albums they've put out be "greatest hits" of some sorts.
1) Van Hagar live
2) Balance (studio)
3) BOV I
4) VH 3 (which SUCKED)
5) Greatest Hits...again.
...doesn't look to me like a band that's exactly overflowing with new material. Why would Dave want to hitch his wagon to a band that is a few more empty stadium shows away from Poison??