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Yep. The scope focuses the light (i.e. intensifies it) so it can do damage inside the scope before it gets to filter, or the filter or EP can be subject to extreme temperatures and fail.
If you have an old EP that you wouldn't mind destroying, you can use it in a Newtonian scope for solar projection into a screen or card, but never look though a scope without a on objective solar filter!
There are also Hershel wedges which dump 95% of the light energy out the back and only allow 5% through. These perform very well for solar imaging, but I don't think they are considered safe these days for visual work (I'll stand corrected by someone more up to speed with a Hershel).
Having seen the damage done to an uncovered finder scope from the sun as it passed over (the finderscope looked like an oxy torch had cut across the back and up the side of the finderscope and the cross hairs were of course gone!), I wouldn't recommend solar work without an objective filter without extreme care, and especially never for visual work.
Al.
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