I know that various codes have had different definitions over the years but, just taking the current FAR's for this discussion:
"VA means design maneuvering speed ....
The maximum operating maneuvering speed, VO, must be established as an operating limitation. VO is a selected speed that is not greater than Vs x sqrt(n) .....
The value of VA need not exceed the value of VC used in design .... VC need not be more than 0.9 VH at sea level."
Maneuver speed for the Pitts S-2A is 154 mph CAS with its max aerobatic weight of 1500 lb. Maneuver speed for the Pitts S-2B is 154 mph CAS with its max aerobatic weight of 1625 lb i.e. less than Vs x sqrt(6) as permitted by the note above regarding 0.9 VH. The Pitts does not reduce VA with reduction in weight, even for those models where VA equals the stall speed at max weight times sqrt (n). From the S-2A Flight Manual:
"... at indicated airspeeds of 154 mph or less, you may apply full aileron, rudder, or nose-up elevator deflection without exceeding the airframe minimum design loads ......" From flight test measurements of an S-2B - the limit load factor of 6 g can be achieved from a sharp pull-up at 140 mph - a function of the dynamic and power effects on maximum lift.
The Decathlon Flight Manual takes a different view.
"Maneuvering speed (VA) is the maximum speed (for an established operating weight) at which full and/or abrupt use of the elevator control will not cause load factors in excess of the +6 G's in Normal Operations or -5 G's in Inverted or Outside Operations.
Full and/or abrupt movement of ailerons may be used at speed up to VA provided that the load factor does not exceed a +4 G's or a -3.2 G's. Use of ailerons above VA or above +4 G's or -3.2 G's should be smooth and limited to deflections which will cause a roll rate not exceeding that roll rate achieved with full aileron at VA.
CAUTION: Full abrupt use of the aileron with simultaneous use of full abrupt elevator at VA may produce loads in excess of design limits."
VA reduces by 3 mph for each 100 lb below maximum weight.
No mention of rudder here.
To give some general guidance for aerobatic pilots, some of us have been developing this Advisory Circular for (too many) years.
AC 91-075(0) - Guidelines for aerobatics (21K Adobe Acrobat file) published September 2001
see Section 10.9
For info on measured flight loads relevant to this subject take a look at
SAE 70002
Pilots are not told enough about flight load limitations due to use of controls - the two examples above are about as good as it gets. The CAP 10B AFM excels in this respect - a short extract:
"Full deflection of any one of the flight controls is authorized up to 146 mph, no matter if you are in negative or positive and with reservation that you are staying in the flight envelope."