Why would LINQ to SQL perform better than a straight SQL query?

public IQueryable<SystemNews> GetSystemNews()
{
    using (var t = new TransactionScope(TransactionScopeOption.Required,
              new TransactionOptions { IsolationLevel = System.Transactions.IsolationLevel.ReadUncommitted }))
    {
        var results = from s in _datacontext.SystemNews
                      let member = GetMemberInfo(s.MemberID)
                      let determination = GetDetermination(s.DeterminationID.Value)
                      let daimoku = GetDaimoku(s.DaimokuID.Value)
                      let entry = GetEntry(s.EntryID.Value)
                      let encouragment = GetEncouragement(s.EncouragementID.Value)
                      select new SystemNews
                      {
                          NewsDate = s.NewsDate,
                          MemberID = s.MemberID,
                          PhotoID = s.PhotoID.Value,
                          DeterminationID = s.DeterminationID.Value,
                          DaimokuID = s.DaimokuID.Value,
                          EntryID = s.EntryID.Value,
                          EncouragementID = s.EncouragementID.Value,
                          Member = new LazyList<Members>(member),
                          Determination = new LazyList<Determinations>(determination),
                          Daimoku = new LazyList<MemberDaimoku>(daimoku),
                          Entry = new LazyList<MemberEntries>(entry),
                          Encouragement = new LazyList<MemberEncouragements>(encouragment),
                          IsDeterminationComplete = s.IsDeterminationComplete.Value
                      };
        return results;
    }
}

_datacontext.Log = Console.Out;