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It is unlikely that caps on the 2HDW are causing this problem. It is far more likely to be bad caps in the power supply. The washed out pix is a CRT bias, screen, or video level problem and could also be related to power supply issues.

You are correct that you should expect that with the convergence output ICs removed, you should have a normal image (with respect to levels) but with no convergence correction.

Start in the power supply. ESR the caps there, check them for capacitance, and look at the output with a scope to see if it is clean. If you can check it, look for DA on the caps.
 

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You will do no damage with the convergence amps removed if all else is working properly. The convergence circuits likely have nothing to do with the washed out image. Whatever is causing that could cause other problems if you run it too much, but there is no way to know without troubleshooting the problem.
 

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Dielectric Absorbtion. This is a measure that will often identify failing caps in these circuits before others and can create some strange effects.
 

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DA can be measured by charging a cap to its rated voltage or near to it, then discharging it through a resistor, then measuring the residual voltage that returns to the terminals of the cap after the resistor is removed. This must be done out of circuit, of course. Another term for DA is battery effect and it should be less than about 15% of the voltage applied.
 
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