Are those tables heaps or clusters?
What's logical fragmentation? forwarding pointers? avg page space used? at the point that you need to do a 'rebuild'?
What version of SQL are you using? What edition?
p.s. How experienced are your DBAs?
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability