The difficulty of changing pace...

So I've been playing HU games (200+10 and 100+5) lately, and have had much success. Mainly because about one in three are soooo bad that it makes up for the other coinflips.--especially since the bad ones usually come back for a rematch.
But every now and then I've done a 5-20 person SNG in between. And I've been smashed to nothingness. I mean I have had 12 winning days averaging about 200 a day (in 3-4h), but I have not won a single 5-20 person SNG in those days(200+10/200+15 about 2 a day). And I have realized what the trouble is: it's switching gears. From the super active aggressive hu to the fold fold fold of the larger SNGs.
So y mix them u ask? Well, my original reason for playing these HU games was to practise reading my opponents and profiling them quickly(which I would then use in my MTTs which is where I win most of my money). But then I thought that probably switching gears is another good thing to work on. So I figured I'd take the opportunity to learn something about that. But it's damn hard. When HU I often call people down with second pair. But in a larger SNG, it seems that this is usually an unneccessary risk, because the reads are so much less dependable(since hu u play a ton of hands more before the blinds rise).
HU the main thing seems to be to decide whether your opponent is too tight or too loose, and in case 1 win small pots and in case 2 win big ones. In tournies it just seems tougher to decide exactly where on the scale everyone lands. Not to mention that the only way to controll who you end up in a pot with--and how many--is to raise. Making it sort of difficult to steal the small pots from the tighties unless they are sitting next to u or one away.
I guess I don't really have a point with this post, just rambling some obvious observations... but if one of ya'll have any insights about this (either about switching gears or reading players shorthanded vrs long or just random thoughts that will bump ur post counts) please share.

I've played a fair number of HU matches. Probably 150-200 over the last year. It's kind of like the difference between playing SnG's vs Ring. You must remind yourself before sitting down, and while playing what you are and are not to do.
HU is a different mentallity for me. I am much more aggressive then I normally am at a 10 person SnG.

I noticed the same pattern myself. I play at lower levels - mostly the Stars 10.50 and 21s 1 ands 2 table games. After about a hundred of these, I have a decent ROI (32%) . HOWEVER, when I switched back to SNG's I went on 220 game downswing, with a single digit ROI that was starting to get to me. Took a week off and to think it through, and figured that I was simply getting into too many hands, because I was used to so much action playing HU.

When I went back, I started to play tighter and open an extra table if things are going too slow for me. ITM and ROI bounced up almost immediately. I know this is at lower levels so not sure how relevant, just my .02