Not really any worse than the others.  It would have been less confusing had they used the range/gear (I.E C2) method, but then you would need a chart like the quad-range to know the speed order is

SR order: 1, 2, 3, 4, 5, 6, 7, 8 or A1, B2, A2, C1, B2, D1, C3, D2
QR order: A1, A2, A3, B1, A4, C1, B2, C2, B3, D1, C3, B4, D2, C4, D3, D4
IH order: L1-TA, L1-D, L2-TA, L2-D, L3-TA, L3-D, L4-TA, H1-TA, L4-D, H1-D,H2-TA,H2-D,H3-TA,H3-D,H4-TA,H4-D
2 cylinder: L1, L2, H1, L3, H2, H3 which later became 1, 2, 3, 4, 5, 6

You could take the IH and have labeled the same with 2,1,R and A,B,C,D.  All three use a 2spd w/r + 4spd to get the 8 gears.  On the QR and IH you add a H/L to double gears by having a 2spd w/r + 4spd + H/L to get 16 gears.

Edit to add:
The SR uses the same concept as the 2 cylinders since it is easier to denote gears in order of ratio for 1-6 or 1-8.  The early numbered 2 cylinder transmission used the neutral position of the 3spd+w/r to shift the H/L while crossing from L-H so the same forward positions occur on both sides of the shift pattern and locks out high reverse (which is physically locked out by the pattern but does exist in the transmission.)

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