I was also advised to fabricate bracing to fit between the a-pillar (hinge pillar) and the B pillar (latch pillar). This was due to the weight of the solution more than anything. It took nearly 3 weeks and several trips through the various baths to remove all the crap on the bodyshell. In the end, I was very pleased with the dipping process, but the cost was easily 3 times what blasting would have been. It was near $4500 to dip my car and I had to drive from North Central Washington (50 miles from Canada) all the way to Portland, Ore. About 750 miles round trip and 4 mountain passes. As it was my personal car, and I was not counting the pennies... I could tolerate it. It's been a year and a half since the car was dipped. I've had no failure of paint or undercoating due to solution creep and I would do it again on a client's car. I dipped a Healey 30 years ago (a 3000 MK2 tri carb 2 seater, one of 141 centershift gearbox cars) at the same place and have had only one area in the frame where I had paint issues due to incomplete neutralization of the dipping solution... It has been easily rectified. Any car that comes in from a rusty climate (anywhere that uses road salt), or has gobs of paint, filler and undercoat, I wouldn't hesitate to recommend having the car dipped. The amount of labor involved to completely strip a car easily exceeds the cost, and in any event, there's nothing that can address internal corrosion.
As these cars are now approaching 60 years of age, there is a lot of stuff you simply cannot see, it makes sense to be a thorough as possible when restoring them. In 40 years, I've had ONE Healey that didn't require new sills and rockers due to internal rot. Knowing how Pressed Steel built bodies, and how Jensen finished them... it's a wonder any of them has lasted this long.
As I have said, many times, the final result and cost have to be taken into account. You get what you pay for.