Later in the month Eduard Lassen – who was to conduct most of the concert at which the Symphony was heard – also recommended the work for performance  (IKRS, 91).

By 22 April Mahler had received notification of the favourable reports on the Symphony and the possibility of a performance from von Bronsart, and replied to indicate that the parts were ready (having been played from) and that he would be happy to conduct the work; in a follow-up letter (24 April) he also reported that the work lasted 48 minutes (IKRS, 93). It was not until early May that Mahler received final confirmation that the work was to be performed, and in his response on 5 May 1894 he made a request about the placing of the work in the programme (IKRS, 94):

This suggestion was ignored: the Symphony was the penultimate item in a very long concert.

On 15 May Mahler was preparing to send the orchestral material to Strauss (who was to conduct the preliminary rehearsals³ ⁴) (GMRSB, 36; GMRSBE, 35):

This crucial letter is not only very revealing about Mahler's creative priorities in undertaking his most recent revisions, but it does provide important clues about the chronology of the process. The 'second copy' with Mahler in Hamburg (ACF2) had been revised and the performing material 'retouched' to reflect these changes, thus rendering the score in Strauss's hands obsolete: the implication that prior to the most recent alterations the two scores were broadly the same confirms the identification of AF2 as the Weimar score.

The fact that the parts ([CO1/CO2]) which were 'fix und fertig' in late April were subsequently retouched, offers strong evidence that, with the possibility of a high-profile performance in the summer confirmed in April, Mahler had taken the opportunity to refine the work, revising ACF2 and collating this score with the performing material. In the case of the opening of the first movement the process, by which Mahler first arrived at and later refined the striking utilization of string harmonics, was complex and as a result the first fascicle of ACF2 preserves two versions of the passage, both of which include layers of revisions (fol. 2r–6v; 7r ff.).

That Mahler should revise this gathering is hardly surprising, but the way in which Weidig incorporated the revision is unusual and may indicate that he was working within a tight schedule. A few other features of this fascicle also require explication. One is that the scoring of the pedal A copied by Weidig onto fol. 7r ff. is not identical to the revised text on fol. 2r ff., indicating that there was one further revision stage, presumably on a document not currently traced; the other is the fact that fol. 7 is a single sheet of type B paper, tipped onto fol. 12. The following is an attempt at a reconstruction of the processes that may have led to these curious features.

As far as Mahler's expansion of the compliment of wind and brass instruments (from triple to quadruple flutes, oboes and clarinets and from four horns to seven) is concerned it is worth noting firstly that Blumine was not modified at all; and secondly that the revision processes used in the other movements differed. In the first third and fourth movements it was Mahler who made the changes, through verbal instruction, changes within existing staves or on spare staves at the top and/or bottom of a page. Some are relatively neat, but many appear to have been written quickly. In the finale, however, the necessary changes are effected for the most part by Weidig. He was evidently working from autographs that outlined the new parts (AR2 and [AR3]; see above) and the revisions, in red ink, were effected with a thoroughly professional concern for clarity and unambiguousness, by verbal instructions, changes within used staves, additions on unused staves, on hand-drawn staves above and/or below the system or on fold-out paste-ons (fol. 87r). Mahler's relatively infrequent additions are not directly concerned with the expansion of the number of wind parts, but rather with other changes in scoring (often neatly done, as on fol. 88v), or performance instructions and some might well reflect alterations made in rehearsal. The result is a score that could be have been used for rehearsal and performance without great difficulty. This difference in revision process suggests that Mahler may have initially planned for the additional instruments to be used only in the finale and that it was only at a later date that he decided to deploy them in the earlier movements. At present there appears to be no conclusive evidence of the date at which any of these changes were made. They may have evolved  as Mahler reviewed the work in advance of Weidig's preparation of ACF3, but if so, why did Weidig and Mahler spend so much time preparing a neat revision of the finale - hardly necessary if Weidig was about to recopy the whole work. But if the revisions date from the run-up to either the Hamburg (1893) or Weimar (1894) performance, why produce a very usable version of the finale, and a much less practical revision of the earlier movements? One explanation would be that at the time of either or both of these performances Mahler did indeed employ the full orchestra only in the finale, and that it was only after 1894, when preparing the 1896, four-movement version, that he expanded the scoring of the rest of the work.

If, as seems more probable than not, the final enlargement of the instrumentation was decided between early autumn 1893 and May 1894, one might have expected Mahler to alert Strauss and the ADM that the work needed more wind instruments than specified in the score they had to hand - particularly since he did indicate that he would like more strings than they were planning to provide (see GMRSB, 36; GMRSBE, 35) - but no evidence has come to light that he did so. However, in the midst of the revisions he was making in the spring of 1894, Mahler seems to have forgotten that the only score to which Strauss had access - AF2  - differed from the new, revised manuscript score and orchestral parts, and that, apart from everything else, it lacked rehearsal numbers: there is something curiously unprofessional in Mahler's asking whether his colleague needs a score that matched the parts in order to be able to rehearse the work. That Mahler expected more than a token run-through or two, is shown by his advice that Strauss undertake sectional rehearsals for wind and strings and one can all-to-easily imagine the frustrating and time-wasting confusion that would have resulted from a set of performing materials that did not match the conductor's score. Strauss's prompt reply has not survived, but he clearly took the eminently pragmatic line that he needed a score that did match the parts, and on 17 May Mahler duly agreed to send ACF2 to Strauss the following day. (GMRSB, 36; GMRSBE, 36; there seems to have been a slight glitch in this process: see Mahler's [undated?] letter to Eugen Lindner quoted in HLG1, 888 fn. 78).

At some stage Mahler may have expected (or at least, hoped) that this score would be the Stichvorlage for a printed edition, as there is more than one Anmerkung für den Setzer (e.g. on fol. 18v); in the event the progress towards publication was rather convoluted and protracted, and two further manuscript copies would be produced (and revised) first (ACF3, ACF4).

The fact that that there are only revisions in black, grey and brown ink (and one pencil annotation) in the second movement, suggest that the revisions using other writing materials may date from a final stage of revisions made after the 1894 performance and/or in preparation for the production of a new four-movement manuscript copy (i.e. ACF3); this possibility is lent some support by the fact that as it now survives ACF2 would be unsuitable for use as a practical conducting score. Sadly, the non-availability of ACF3 makes the identification of the final textual layer in ACF2 difficult (if not impossible) to ascertain with any degree of certainty.