those are good points. clear-coat brushes should always be strictly for clear. i have learned the hard way over the years of production painting, that brushes should always be paint-type specific. oil brushes are always for oils, acrylic brushes are always for acrylics, clears always for clears.
to take it a step further, if you take certain steps in care for your brushes, they will last for years and not get dried out and the bristles will stay compact. for oils and/or enamels, when you are finished with your brushes, dip them in motor oil, yes, motor oil. it keeps the paint from drying out in your ferrule causing the bristles to seperate and ruin the brush. for acrylics, use dish soap in the same way. and always clean your brush before using
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