Your theory of a surprise assault on the marshes.... Try running it backwards..... Calculate the figure of the specific number of aircraft, helicopters and amphibious craft that will be required for such an operation....
... Then try assembling then at a place for launch
... Then calculate the troops as well, and also decide from which cantonments these troops will move to assemble...
... Then see whether such a big and assembly of such equipment can be hidden.... That too in today's environment where HUMINT is not the only source of info.
Nature of military intelligence suggests that minor troop movements are not picked up, and even if picked up, is discarded as static noise. This allows an attack on Bhuj. Consider the following:
1. 20x helicopters taking off from various locations
2. One battalion from Karoonjar
3. 5 hovercrafts over Karoonjar adjacent lake
4. Rangers remain relativley undetected as they are spread out, and expected to operate near the border. 10x ranger companies from diverse vectors all along the Bhuj salient
5. Marines ingressing through the sea and the Rann of Kutch inlet - different vector. Say, 4 companies equivalent
6. An army division begins preparations for attack and zero hour, so attack is already under way by the time this division begins moving - meaning at least 1 hour later Indians become aware - but by then forces 1-5 have already been in Indian territory for an hour.
7. Airborne assault - paratroopers - 5 companies equivalent.
8. Massive airstrikes launched by PAF - say 30 minutes into the assault.
9. Hide artillery in Karoonjar mountains and place them at altitude for long range fire support - can literally cover all major salients of Bhuj.
Each of these, except for (6) is by itself too small for the Indians to take note. However, their cumulative effect is a sudden shock, reinforced by the heavy fist of the PA division now coming in to reinforce the initial assault.
*** If I had it my way - An-2 assault teams could also partake in this venture.