Well, healing surges and such are also kind of an issue.
The real question is, does it solve the problem you're having? Is it a problem with the way the game organizes resource management or is it just that the encounters presented to the PCs are demanding that they expend daily resources in every encounter?
Suppose the encounters in your campaign mostly all require daily expenditure to defeat. Giving everyone 4 daily uses per day will get them through, at least at low levels. But they WILL probably just burn their dailies as fast as they can. Now you pretty much HAVE to make every encounter considerably more challenging in order to provide balance. Two problems can arise. One is that instead of running out of dailies the characters will likely run out of healing surges. Secondly once they get to higher levels (around 9th level) 4 daily uses will put you back in the same boat since a 9th level character already gets 3 dailies and even 5th level characters may well have 2 daily and a utility power with daily use.
So it becomes an interesting question. Is it better to tweak the resource use rules, or is it maybe possible to let the character's stretch out their day by providing a more scaled set of encounters? Players really shouldn't have to trigger daily use when facing lesser challenges. A 5th level party SHOULD be able to beat most 5th level encounters without absolutely needing to use daily powers. Maybe sometimes they WILL use one, but they should be doing so as a conscious trade off where they decide to preserve some other resource like surges or magic item daily use against it.
Consider if a party faces 4 encounters in a day, and I'd say few parties will ever manage much beyond that regardless of resource use restrictions, the adventure construction guidelines would say that the mix would be something like this. 1-2 of the encounters will be puzzles or skill challenges. These don't usually burn a lot of resources and tend to burn surges if they do. Of the 2-3 combat encounters they'll likely face one is likely to be level-1 or level, one is likely to be level+1 or level+2, and maybe the final one might be level+3 or level+4.
The final level+3-4 encounter is definitely where characters will want to burn their dailies and whatnot. It should be challenging enough that they probably need to do so in order to make it through unless they are really clever or very lucky.
The day's easy encounter shouldn't require any daily use, unless the party has horrible luck or are really bone headed. It will probably eat up a few surges and provide some kind of interesting tactical situation or introduce some new type of monster, etc. It is intended to be a way of providing variety and dramatic tension, not a great deal of risk. Lurker monsters are great for those btw. They say "boo!" to the party, hurt a couple people a bit, then die or run off.
The standard difficulty level and level+1 type encounters can do all sorts of things. They will tempt players to burn valuable resources and take out enough surges to give them a bit of anxiety usually, but not actually reduce their fighting ability much.
So, IMHO careful encounter design and adventure pacing should obviate most of the 15 minute adventuring day. For those times when you want to be SURE the PCs are in a tense situation and can't rest, give them a plot reason. Don't overuse it, but it is there when you want to have a change of pace.
Running 4e seems to demand a lot from DMs. I'm not saying nerfing resource management is some kind of 'badwrongfun' or anything like that, but the real ultimate DM skill test is to run it as designed and be able to keep the party going forward just fast enough to make them worried about resources, but not quite willing to stop.
